sunxi: prepare for sharing MACH_SUN8I_H3 config symbol

The Allwinner H5 is very close to the H3 SoC, but has ARMv8 cores.
To allow sharing the clocks, GPIO and driver code easily, create an
architecture agnostic MACH_SUNXI_H3_H5 Kconfig symbol.
Rename the existing symbol to MACH_SUNXI_H3_H5 where code is shared and
let it be selected by a new shared Kconfig option.

Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Acked-by: Maxime Ripard <maxime.ripard@free-electrons.com>
diff --git a/drivers/mtd/spi/Kconfig b/drivers/mtd/spi/Kconfig
index 1f23c8e..5ca0a71 100644
--- a/drivers/mtd/spi/Kconfig
+++ b/drivers/mtd/spi/Kconfig
@@ -132,7 +132,7 @@
 
 config SPL_SPI_SUNXI
 	bool "Support for SPI Flash on Allwinner SoCs in SPL"
-	depends on MACH_SUN4I || MACH_SUN5I || MACH_SUN7I || MACH_SUN8I_H3 || MACH_SUN50I
+	depends on MACH_SUN4I || MACH_SUN5I || MACH_SUN7I || MACH_SUNXI_H3_H5 || MACH_SUN50I
 	---help---
 	Enable support for SPI Flash. This option allows SPL to read from
 	sunxi SPI Flash. It uses the same method as the boot ROM, so does