Restrict adc_multi example to STM32L0x2

It doesn't compile on the other targets.

Author: hannobraun

Cargo.toml

@@ -266,6 +266,10 @@ opt-level = "s"
 name = "adc_cont"
 required-features = ["stm32l0x2"]
 
+[[example]]
+name = "adc_multi"
+required-features = ["stm32l0x2"]
+
 [[example]]
 name = "adc_trig"
 required-features = ["stm32l0x2"]