Kconfigs: Correct default of "0" on hex type entries

It is not a parse error to have a default value of "0" for a "hex" type
entry, instead of "0x0".  However, "0" and "0x0" are not treated the
same even by the tools themselves. Correct this by changing the default
value from "0" to "0x0" for all hex type questions that had the
incorrect default. Fix one instance (in two configs) of a default of "0"
being used on a hex question to be "0x0". Remove the cases where a
defconfig had set a value of "0x0" to be used as the default had been
"0".

Signed-off-by: Tom Rini <trini@konsulko.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
diff --git a/env/Kconfig b/env/Kconfig
index 13e3210..54203fa 100644
--- a/env/Kconfig
+++ b/env/Kconfig
@@ -571,7 +571,7 @@
 	default 0xE0000 if ARCH_ZYNQ
 	default 0x1E00000 if ARCH_ZYNQMP
 	default 0x7F40000 if ARCH_VERSAL || ARCH_VERSAL_NET
-	default 0 if ARC
+	default 0x0 if ARC
 	default 0x140000 if ARCH_AT91
 	default 0x260000 if ARCH_OMAP2PLUS
 	default 0x1080000 if MICROBLAZE && ENV_IS_IN_SPI_FLASH
@@ -583,7 +583,7 @@
 	depends on (ENV_IS_IN_EEPROM || ENV_IS_IN_MMC || ENV_IS_IN_NAND || \
 		    ENV_IS_IN_SPI_FLASH) && SYS_REDUNDAND_ENVIRONMENT
 	default 0x10C0000 if MICROBLAZE
-	default 0
+	default 0x0
 	help
 	  Offset from the start of the device (or partition) of the redundant
 	  environment location.