Staging: sm750fb: Change *array into *const array

Resolve checkpatch warning for static const char * array by using const
pointers.

Checkpatch Warning in sm750.c:
static const char * array should probably be static const char * const
Signed-off-by: Kelsey Skunberg <skunberg.kelsey@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/staging/sm750fb/sm750.c

@@ -748,7 +748,7 @@ static int lynxfb_set_fbinfo(struct fb_info *info, int index)
 		lynx750_ext, NULL, vesa_modes,
 	};
 	int cdb[] = {ARRAY_SIZE(lynx750_ext), 0, VESA_MODEDB_SIZE};
-	static const char *mdb_desc[] = {
+	static const char * const mdb_desc[] = {
 		"driver prepared modes",
 		"kernel prepared default modedb",
 		"kernel HELPERS prepared vesa_modes",