x86, microcode, AMD: Replace vmalloc+memset with vzalloc

We don't have to do memset() ourselves after vmalloc() when we have
vzalloc(), so change that in
arch/x86/kernel/microcode_amd.c::get_next_ucode().

Signed-off-by: Jesper Juhl <jj@chaosbits.net>
Signed-off-by: Borislav Petkov <borislav.petkov@amd.com>
diff --git a/arch/x86/kernel/microcode_amd.c b/arch/x86/kernel/microcode_amd.c
index e1af7c0..383d4f8 100644
--- a/arch/x86/kernel/microcode_amd.c
+++ b/arch/x86/kernel/microcode_amd.c
@@ -183,16 +183,17 @@
 		return NULL;
 	}
 
-	mc = vmalloc(UCODE_MAX_SIZE);
-	if (mc) {
-		memset(mc, 0, UCODE_MAX_SIZE);
-		if (get_ucode_data(mc, buf + UCODE_CONTAINER_SECTION_HDR,
-				   total_size)) {
-			vfree(mc);
-			mc = NULL;
-		} else
-			*mc_size = total_size + UCODE_CONTAINER_SECTION_HDR;
+	mc = vzalloc(UCODE_MAX_SIZE);
+	if (!mc)
+		return NULL;
+
+	if (get_ucode_data(mc, buf + UCODE_CONTAINER_SECTION_HDR, total_size)) {
+		vfree(mc);
+		mc = NULL;
+	} else {
+		*mc_size = total_size + UCODE_CONTAINER_SECTION_HDR;
 	}
+
 	return mc;
 }