libfdt.h: typo and consistency fixes

Most of these are plain typos. Exceptions:

- "devicetree" is only used in that form in the grammar and in mailing
  list references; all other instances, in particular all in prose,
  use "device tree".

- I don't know what "nodeequested" was supposed to be, the sentence
  reads just fine without it.

- "inexistant" is a rare form of nonexistent.

libfdt/libfdt.h

@@ -285,7 +285,7 @@ size_t fdt_header_size(const void *fdt);
 
 /**
  * fdt_header_size_ - internal function to get header size from a version number
- * @version: devicetree version number
+ * @version: device tree version number
  *
  * Return: size of DTB header in bytes
  */
@@ -764,15 +764,15 @@ static inline struct fdt_property *fdt_get_property_w(void *fdt, int nodeoffset,
  * to within the device blob itself, not a copy of the value).  If
  * lenp is non-NULL, the length of the property value is also
  * returned, in the integer pointed to by lenp.  If namep is non-NULL,
- * the property's namne will also be returned in the char * pointed to
+ * the property's name will also be returned in the char * pointed to
  * by namep (this will be a pointer to within the device tree's string
  * block, not a new copy of the name).
  *
  * returns:
  *	pointer to the property's value
  *		if lenp is non-NULL, *lenp contains the length of the property
  *		value (>=0)
- *		if namep is non-NULL *namep contiains a pointer to the property
+ *		if namep is non-NULL *namep contains a pointer to the property
  *		name.
  *	NULL, on error
  *		if lenp is non-NULL, *lenp contains an error code (<0):
@@ -866,7 +866,7 @@ uint32_t fdt_get_phandle(const void *fdt, int nodeoffset);
 /**
  * fdt_get_alias_namelen - get alias based on substring
  * @fdt: pointer to the device tree blob
- * @name: name of the alias th look up
+ * @name: name of the alias to look up
  * @namelen: number of characters of name to consider
  *
  * Identical to fdt_get_alias(), but only examine the first @namelen
@@ -883,7 +883,7 @@ const char *fdt_get_alias_namelen(const void *fdt,
 /**
  * fdt_get_alias - retrieve the path referenced by a given alias
  * @fdt: pointer to the device tree blob
- * @name: name of the alias th look up
+ * @name: name of the alias to look up
  *
  * fdt_get_alias() retrieves the value of a given alias.  That is, the
  * value of the property named @name in the node /aliases.
@@ -1698,7 +1698,7 @@ int fdt_setprop(void *fdt, int nodeoffset, const char *name,
  * @len: length of the property value
  * @prop_data: return pointer to property data
  *
- * fdt_setprop_placeholer() allocates the named property in the given node.
+ * fdt_setprop_placeholder() allocates the named property in the given node.
  * If the property exists it is resized. In either case a pointer to the
  * property data is returned.
  *
@@ -2059,7 +2059,7 @@ int fdt_appendprop_addrrange(void *fdt, int parent, int nodeoffset,
  * @nodeoffset: offset of the node whose property to nop
  * @name: name of the property to nop
  *
- * fdt_del_property() will delete the given property.
+ * fdt_delprop() will delete the given property.
  *
  * This function will delete data from the blob, and will therefore
  * change the offsets of some existing nodes.
@@ -2111,8 +2111,7 @@ int fdt_add_subnode_namelen(void *fdt, int parentoffset,
  * change the offsets of some existing nodes.
  *
  * returns:
- *	structure block offset of the created nodeequested subnode (>=0), on
- *		success
+ *	structure block offset of the created subnode (>=0), on success
  *	-FDT_ERR_NOTFOUND, if the requested subnode does not exist
  *	-FDT_ERR_BADOFFSET, if parentoffset did not point to an FDT_BEGIN_NODE
  *		tag
@@ -2167,7 +2166,7 @@ int fdt_del_node(void *fdt, int nodeoffset);
  * returns:
  *	0, on success
  *	-FDT_ERR_NOSPACE, there's not enough space in the base device tree
- *	-FDT_ERR_NOTFOUND, the overlay points to some inexistant nodes or
+ *	-FDT_ERR_NOTFOUND, the overlay points to some nonexistent nodes or
  *		properties in the base DT
  *	-FDT_ERR_BADPHANDLE,
  *	-FDT_ERR_BADOVERLAY,