rcc: uncomment SYSCFG support (#123)

Author: agalakhov

src/rcc/enable.rs

@@ -115,7 +115,6 @@ bus! {
     USART2 => (APB1, usart2en, usart2smen, usart2rst), // 17
     WWDG => (APB1, wwdgen, wwdgsmen,), // 11
 
-    //SYSCFG => (APB2, syscfgen, syscfgsmen, syscfgrst), // 0
     ADC => (APB2, adcen, adcsmen, adcrst), // 20
     SPI1 => (APB2, spi1en, spi1smen, spi1rst), // 12
     TIM1 => (APB2, tim1en, tim1smen, tim1rst), // 11
@@ -131,6 +130,11 @@ bus! {
     GPIOF => (IOP, iopfen, iopfsmen, iopfrst), // 5
 }
 
+#[cfg(any(feature = "stm32g030", feature = "stm32g031", feature = "stm32g041"))]
+bus! {
+    SYSCFG => (APB2, syscfgen, syscfgsmen, syscfgrst), // 0
+}
+
 #[cfg(any(feature = "stm32g041", feature = "stm32g081"))]
 bus! {
     AES => (AHB, aesen, aessmen, aesrst), // 16