config: do not use deprecated stm32.cfg

Change-Id: Id72d2d7f874043331ecb5586a3797d017606129e
Signed-off-by: Spencer Oliver <spen@spen-soft.co.uk>
Signed-off-by: Felix Ruess <felix.ruess@gmail.com>
Reviewed-on: http://openocd.zylin.com/212
Tested-by: jenkins

tcl/board/lisa-l.cfg

@@ -4,4 +4,4 @@
 # Work-area size (RAM size) = 20kB for STM32F103RB device
 set WORKAREASIZE 0x5000
 
-source [find target/stm32.cfg]
+source [find target/stm32f1x.cfg]