Due to a previously change of the partition namings, the kernel- and
oftree-paths in the SPI-bootscript have to be adapted to the changes.

The previous change can be found here:
commit 72ba815

Signed-off-by: Yunus Bas <y.bas@phytec.de>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

Rename sd-ext3 to mmc, remove filesystem type from bootargs and remove
bootargs-ip. Add init script 'bootsource' to set boot source priority
and bootscript 'spi' for SPI NOR.

Signed-off-by: Christian Hemp <c.hemp@phytec.de>
Signed-off-by: Stefan Christ <s.christ@phytec.de>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>