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/drivers/amd/agesa/romstage.c b/src/drivers/amd/agesa/romstage.c
index 5c3d904..132cb3e 100644
--- a/src/drivers/amd/agesa/romstage.c
+++ b/src/drivers/amd/agesa/romstage.c
@@ -93,8 +93,8 @@
 	halt();
 }
 
-void *cbmem_top_chipset(void)
+uintptr_t cbmem_top_chipset(void)
 {
 	/* Top of CBMEM is at highest usable DRAM address below 4GiB. */
-	return (void *)restore_top_of_low_cacheable();
+	return restore_top_of_low_cacheable();
 }