cbmem_top_chipset: Change the return value to uintptr_t

Get rid of a lot of casts.

Change-Id: I93645ef5dd270905ce421e68e342aff4c331eae6
Signed-off-by: Elyes Haouas <ehaouas@noos.fr>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/69078
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Jakub Czapiga <jacz@semihalf.com>
diff --git a/src/soc/qualcomm/sc7180/cbmem.c b/src/soc/qualcomm/sc7180/cbmem.c
index 4b9eb37..5fff371 100644
--- a/src/soc/qualcomm/sc7180/cbmem.c
+++ b/src/soc/qualcomm/sc7180/cbmem.c
@@ -2,7 +2,7 @@
 
 #include <cbmem.h>
 
-void *cbmem_top_chipset(void)
+uintptr_t cbmem_top_chipset(void)
 {
-	return (void *)((uintptr_t)4 * GiB);
+	return (uintptr_t)4 * GiB;
 }