mmc: clean up help texts

Remove some repeated words and superfluous newlines in the mmc command
help entries.

Signed-off-by: Rabin Vincent <rabin@rab.in>

common/cmd_mmc.c

@@ -135,8 +135,9 @@ int do_mmcinfo (cmd_tbl_t *cmdtp, int flag, int argc, char *argv[])
 	return 0;
 }
 
-U_BOOT_CMD(mmcinfo, 2, 0, do_mmcinfo, "mmcinfo <dev num>-- display MMC info\n",
-		NULL);
+U_BOOT_CMD(mmcinfo,	2,	0,	do_mmcinfo,
+	"print MMC information",
+	"<dev num>\n");
 
 int do_mmcops(cmd_tbl_t *cmdtp, int flag, int argc, char *argv[])
 {
@@ -218,8 +219,8 @@ int do_mmcops(cmd_tbl_t *cmdtp, int flag, int argc, char *argv[])
 U_BOOT_CMD(
 	mmc, 6, 1, do_mmcops,
 	"MMC sub system",
-	"mmc read <device num> addr blk# cnt\n"
+	"read <device num> addr blk# cnt\n"
 	"mmc write <device num> addr blk# cnt\n"
 	"mmc rescan <device num>\n"
-	"mmc list - lists available devices\n");
+	"mmc list - list available devices\n");
 #endif