Update Linux max phys mem write size from 0xFFFF to 0xFFFFFFFF

Signed-off-by: Nathaniel Mitchell <[email protected]>

chipsec/helper/linux/linuxhelper.py

@@ -242,7 +242,7 @@ def __mem_block(self, sz: int, newval: Optional[bytes] = None) -> bytes:
             else:
                 res = self.dev_fh.write(newval)
                 self.dev_fh.flush()
-                return res.to_bytes(2, 'little')
+                return res.to_bytes(4, 'little')
         return b''
 
     def write_phys_mem(self, phys_address: int, length: int, newval: bytes) -> int: