efi_loader: consistently use efi_uintn_t in boot services

Consistenly use efi_uintn_t wherever the UEFI spec uses
UINTN in boot services interfaces.

Signed-off-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
Signed-off-by: Alexander Graf <agraf@suse.de>
diff --git a/lib/efi_selftest/efi_selftest_snp.c b/lib/efi_selftest/efi_selftest_snp.c
index bdd6ce2..cc0705f 100644
--- a/lib/efi_selftest/efi_selftest_snp.c
+++ b/lib/efi_selftest/efi_selftest_snp.c
@@ -260,7 +260,7 @@
 {
 	efi_status_t ret;
 	struct efi_event *events[2];
-	size_t index;
+	efi_uintn_t index;
 	union {
 		struct dhcp p;
 		u8 b[PKTSIZE];