ARMv7M: add STM32F1 support

Add ARMv7M STM32F1 support including clocks, timer, gpio, and flash.

Signed-off-by: Matt Porter <mporter@konsulko.com>
diff --git a/include/flash.h b/include/flash.h
index 48aa3a5..5754cf9 100644
--- a/include/flash.h
+++ b/include/flash.h
@@ -460,6 +460,7 @@
 #define FLASH_S29GL128N 0x00F1		/* Spansion S29GL128N			*/
 
 #define FLASH_STM32F4	0x00F2		/* STM32F4 Embedded Flash */
+#define FLASH_STM32F1	0x00F3		/* STM32F1 Embedded Flash */
 
 #define FLASH_UNKNOWN	0xFFFF		/* unknown flash type			*/