stm32l0: land adc-v2 peripheral support

Now that the big pieces of the adc-v2 common files are in place, start
including l0 in the builds.  This includes only the very very basic core v2
peripheral functions, and the very basic definitions.

lib/stm32/l0/Makefile

@@ -39,6 +39,7 @@ OBJS		= gpio.o rcc.o desig.o
 OBJS		+= pwr_common_all.o pwr_common_l01.o
 
 OBJS            += gpio_common_all.o gpio_common_f0234.o rcc_common_all.o
+OBJS		+= adc_common_v2.o
 OBJS		+= crs_common_all.o
 
 OBJS            += usb.o usb_control.o usb_standard.o