qte-toolchain-target: update depenencies

- disable qwt for now, causing unresolved build errors
- add gpsd-dev for APC development

Signed-off-by: Björn Krombholz <b.krombholz@pironex.de>
linux-ti33x-psp_3.2: add CMUX support

- enable N_GSM support (used on boards with UART connected GSM)

Signed-off-by: Björn Krombholz <b.krombholz@pironex.de>
pia-am335x-apc: update default uboot branch

Signed-off-by: Björn Krombholz <b.krombholz@pironex.de>