mimxrt1050_evk: Update jlink device name
mimxrt1050_evk: Update jlink device name

A bug in the jlink application made it impossible to use OpenSDA
firmware with the mimxrt1052 device name, so we used the generic
Cortex-M7 device name as a workaround. This bug was fixed in jlink
V6.32h (2018-07-05), so now we can use the more specific device name.

Signed-off-by: Maureen Helm <87a696db5547fa477bda9f9e0f00013c839c14d3@nxp.com>

galak/zephyr,GiulianoFranchetto/zephyr,ldts/zephyr,nashif/zephyr,punitvara/zephyr,finikorg/zephyr,galak/zephyr,galak/zephyr,kraj/zephyr,galak/zephyr,explora26/zephyr,kraj/zephyr,explora26/zephyr,Vudentz/zephyr,zephyrproject-rtos/zephyr,GiulianoFranchetto/zephyr,kraj/zephyr,punitvara/zephyr,kraj/zephyr,Vudentz/zephyr,punitvara/zephyr,ldts/zephyr,punitvara/zephyr,Vudentz/zephyr,nashif/zephyr,Vudentz/zephyr,zephyrproject-rtos/zephyr,Vudentz/zephyr,GiulianoFranchetto/zephyr,nashif/zephyr,explora26/zephyr,finikorg/zephyr,zephyrproject-rtos/zephyr,kraj/zephyr,explora26/zephyr,zephyrproject-rtos/zephyr,Vudentz/zephyr,nashif/zephyr,finikorg/zephyr,GiulianoFranchetto/zephyr,nashif/zephyr,ldts/zephyr,ldts/zephyr,GiulianoFranchetto/zephyr,finikorg/zephyr,zephyrproject-rtos/zephyr,punitvara/zephyr,ldts/zephyr,finikorg/zephyr,galak/zephyr,explora26/zephyr