include/asm-generic/io.h: fix kerneldoc markup

Kerneldoc requires a "-" after the name of a function for it
to be recognized as a function.

Add it.

Fix those kernel-doc warnings:

include/asm-generic/io.h:1215: warning: This comment starts with '/**', but isn't a kernel-doc comment. Refer Documentation/doc-guide/kernel-doc.rst
 * memset_io    Set a range of I/O memory to a constant value
include/asm-generic/io.h:1227: warning: This comment starts with '/**', but isn't a kernel-doc comment. Refer Documentation/doc-guide/kernel-doc.rst
 * memcpy_fromio        Copy a block of data from I/O memory
include/asm-generic/io.h:1239: warning: This comment starts with '/**', but isn't a kernel-doc comment. Refer Documentation/doc-guide/kernel-doc.rst
 * memcpy_toio          Copy a block of data into I/O memory

Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Link: https://lore.kernel.org/r/066968c00196ed88f6dc97e3d317926fc4ab7d52.1740387599.git.mchehab+huawei@kernel.org
Signed-off-by: Jonathan Corbet <corbet@lwn.net>

Author: mchehab

include/asm-generic/io.h

@@ -1212,7 +1212,7 @@ static inline void unxlate_dev_mem_ptr(phys_addr_t phys, void *addr)
 
 #ifndef memset_io
 /**
- * memset_io	Set a range of I/O memory to a constant value
+ * memset_io -	Set a range of I/O memory to a constant value
  * @addr:	The beginning of the I/O-memory range to set
  * @val:	The value to set the memory to
  * @count:	The number of bytes to set
@@ -1224,7 +1224,7 @@ void memset_io(volatile void __iomem *addr, int val, size_t count);
 
 #ifndef memcpy_fromio
 /**
- * memcpy_fromio	Copy a block of data from I/O memory
+ * memcpy_fromio -	Copy a block of data from I/O memory
  * @dst:		The (RAM) destination for the copy
  * @src:		The (I/O memory) source for the data
  * @count:		The number of bytes to copy
@@ -1236,7 +1236,7 @@ void memcpy_fromio(void *dst, const volatile void __iomem *src, size_t count);
 
 #ifndef memcpy_toio
 /**
- * memcpy_toio		Copy a block of data into I/O memory
+ * memcpy_toio -	Copy a block of data into I/O memory
  * @dst:		The (I/O memory) destination for the copy
  * @src:		The (RAM) source for the data
  * @count:		The number of bytes to copy