cmd_ext4: remove TABs from command help text

TABs in the help text won't line up in the same place on the console as
in a source editor. Replace them with spaces to make ensuring correct
alignment easier.

Signed-off-by: Stephen Warren <swarren@nvidia.com>
Reviewed-by: Benoît Thébaudeau <benoit.thebaudeau@advansee.com>

common/cmd_ext4.c

@@ -123,17 +123,17 @@ fail:
 U_BOOT_CMD(ext4write, 6, 1, do_ext4_write,
 	"create a file in the root directory",
 	"<interface> <dev[:part]> [Absolute filename path] [Address] [sizebytes]\n"
-	"	  - create a file in / directory");
+	"    - create a file in / directory");
 
 #endif
 
 U_BOOT_CMD(ext4ls, 4, 1, do_ext4_ls,
 	   "list files in a directory (default /)",
 	   "<interface> <dev[:part]> [directory]\n"
-	   "	  - list files from 'dev' on 'interface' in a 'directory'");
+	   "    - list files from 'dev' on 'interface' in a 'directory'");
 
 U_BOOT_CMD(ext4load, 6, 0, do_ext4_load,
 	   "load binary file from a Ext4 filesystem",
 	   "<interface> <dev[:part]> [addr] [filename] [bytes]\n"
-	   "	  - load binary file 'filename' from 'dev' on 'interface'\n"
-	   "		 to address 'addr' from ext4 filesystem");
+	   "    - load binary file 'filename' from 'dev' on 'interface'\n"
+	   "      to address 'addr' from ext4 filesystem");