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/ipq40xx/cbmem.c b/src/soc/qualcomm/ipq40xx/cbmem.c
index 0ee9f9a..c5d1a81 100644
--- a/src/soc/qualcomm/ipq40xx/cbmem.c
+++ b/src/soc/qualcomm/ipq40xx/cbmem.c
@@ -10,7 +10,7 @@
 	cbmem_backing_store_ready = 1;
 }
 
-void *cbmem_top_chipset(void)
+uintptr_t cbmem_top_chipset(void)
 {
 	/*
 	 * In romstage, make sure that cbmem backing store is ready before
@@ -19,7 +19,7 @@
 	 * for loading ipq blobs before DRAM is initialized).
 	 */
 	if (cbmem_backing_store_ready == 0)
-		return NULL;
+		return 0;
 
-	return _memlayout_cbmem_top;
+	return (uintptr_t)_memlayout_cbmem_top;
 }