Remove volatile qualifier in get_ram_size() calls

Checkpatch.pl complains about the volatile qualifier in calls to
get_ram_size(). Remove this qualifier in the prototype and in the
calls where it is useless, and leave it only in the function body
where it is needed.

Signed-off-by: Albert ARIBAUD <albert.u.boot@aribaud.net>
diff --git a/board/freescale/mx53smd/mx53smd.c b/board/freescale/mx53smd/mx53smd.c
index f3c433f..21b5d14 100644
--- a/board/freescale/mx53smd/mx53smd.c
+++ b/board/freescale/mx53smd/mx53smd.c
@@ -44,8 +44,8 @@
 {
 	u32 size1, size2;
 
-	size1 = get_ram_size((volatile void *)PHYS_SDRAM_1, PHYS_SDRAM_1_SIZE);
-	size2 = get_ram_size((volatile void *)PHYS_SDRAM_2, PHYS_SDRAM_2_SIZE);
+	size1 = get_ram_size((void *)PHYS_SDRAM_1, PHYS_SDRAM_1_SIZE);
+	size2 = get_ram_size((void *)PHYS_SDRAM_2, PHYS_SDRAM_2_SIZE);
 
 	gd->ram_size = size1 + size2;