misc: microchip_flexcom: introduce microchip_flexcom driver

The Microchip Flexcom is just a wrapper which embeds a SPI controller,
an I2C controller and an USART.
Only one function can be used at a time and is chosen at boot time according
to the device tree.
The bindings are kept as in Linux.
The driver registers to MISC_UCLASS.

Signed-off-by: Eugen Hristev <eugen.hristev@microchip.com>
diff --git a/drivers/misc/Makefile b/drivers/misc/Makefile
index 0001d10..f612636 100644
--- a/drivers/misc/Makefile
+++ b/drivers/misc/Makefile
@@ -65,3 +65,4 @@
 obj-$(CONFIG_VEXPRESS_CONFIG) += vexpress_config.o
 obj-$(CONFIG_WINBOND_W83627) += winbond_w83627.o
 obj-$(CONFIG_JZ4780_EFUSE) += jz4780_efuse.o
+obj-$(CONFIG_MICROCHIP_FLEXCOM) += microchip_flexcom.o