allwinner: Synchronize PMIC enumerations

Ensure that the default (zero) value represents the case where we take
no action. Previously, if a PLAT=sun50i_a64 build was booted on an
unknown SoC ID, it would be treated as an H5 at shutdown.

This removes some duplicate code and fixes error propagation on H6.
Signed-off-by: Samuel Holland <samuel@sholland.org>
Change-Id: I4e51d8a43a56eccb0d8088593cb9908e52e782bc

plat/allwinner/sun50i_a64/sunxi_power.c

 /*
- * Copyright (c) 2017-2018, ARM Limited and Contributors. All rights reserved.
+ * Copyright (c) 2017-2019, ARM Limited and Contributors. All rights reserved.
  * Copyright (c) 2018, Icenowy Zheng <icenowy@aosc.io>
  *
  * SPDX-License-Identifier: BSD-3-Clause
@@ -22,6 +22,7 @@
 #include <sunxi_private.h>
 
 static enum pmic_type {
+	UNKNOWN,
 	GENERIC_H5,
 	GENERIC_A64,
 	REF_DESIGN_H5,	/* regulators controlled by GPIO pins on port L */

plat/allwinner/sun50i_h6/sunxi_power.c

 /*
- * Copyright (c) 2017-2018, ARM Limited and Contributors. All rights reserved.
+ * Copyright (c) 2017-2019, ARM Limited and Contributors. All rights reserved.
  * Copyright (c) 2018, Icenowy Zheng <icenowy@aosc.io>
  *
  * SPDX-License-Identifier: BSD-3-Clause
@@ -21,12 +21,10 @@
 #define AXP805_ADDR	0x36
 #define AXP805_ID	0x03
 
-enum pmic_type {
-	NO_PMIC,
+static enum pmic_type {
+	UNKNOWN,
 	AXP805,
-};
-
-enum pmic_type pmic;
+} pmic;
 
 int axp_i2c_read(uint8_t chip, uint8_t reg, uint8_t *val)
 {
@@ -79,12 +77,11 @@ int sunxi_pmic_setup(uint16_t socid, const void *fdt)
 	i2c_init((void *)SUNXI_R_I2C_BASE);
 
 	NOTICE("PMIC: Probing AXP805\n");
-	pmic = AXP805;
 
 	ret = axp805_probe();
 	if (ret)
-		pmic = NO_PMIC;
-	else
+		return ret;
+
 	pmic = AXP805;
 
 	return 0;