stm32flash: fix help text format

Warning reported by check-package.

Signed-off-by: Luca Ceresoli <luca@lucaceresoli.net>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>

package/stm32flash/Config.in

@@ -2,7 +2,7 @@ config BR2_PACKAGE_STM32FLASH
 	bool "stm32flash"
 	help
 	  Open source cross platform flash program for the STM32 ARM
-	  microcontrollers using the built-in ST serial bootloader over UART
-	  or I2C.
+	  microcontrollers using the built-in ST serial bootloader
+	  over UART or I2C.
 
 	  http://sourceforge.net/projects/stm32flash/