mmc: Standardize header file inclusion checks.

Standardize the checks for multiple MMC header file inclusion,
including adding comments to terminating #endif's, and fixing
one incorrect comment.

Signed-off-by: Robert P. J. Day <rpjday@crashcourse.ca>
Signed-off-by: Chris Ball <cjb@laptop.org>
diff --git a/include/linux/mmc/sdio.h b/include/linux/mmc/sdio.h
index 245cdac..2a2e990 100644
--- a/include/linux/mmc/sdio.h
+++ b/include/linux/mmc/sdio.h
@@ -9,8 +9,8 @@
  * your option) any later version.
  */
 
-#ifndef MMC_SDIO_H
-#define MMC_SDIO_H
+#ifndef LINUX_MMC_SDIO_H
+#define LINUX_MMC_SDIO_H
 
 /* SDIO commands                         type  argument     response */
 #define SD_IO_SEND_OP_COND          5 /* bcr  [23:0] OCR         R4  */
@@ -161,5 +161,4 @@
 
 #define SDIO_FBR_BLKSIZE	0x10	/* block size (2 bytes) */
 
-#endif
-
+#endif /* LINUX_MMC_SDIO_H */