pia-am335x-eb-tft: add board type check for EB_TFT

Signed-off-by: Björn Krombholz <b.krombholz@pironex.de>
pia-am335x-eb-tft: enable backup battery charger

- turn on TPS battery charger on firststart
- TODO (re)enable it on normal boot

Signed-off-by: Björn Krombholz <b.krombholz@pironex.de>
pia-am335x: fix DDR initialization for piA-AM335x...

- revert BeagleBone testing code which enabled DDR2 mode
- piA-AM335x boards use DDR3 memory only

Signed-off-by: Björn Krombholz <b.krombholz@pironex.de>
Merge commit '8b5b7bc268f3c0b0548ad911395242ab375ffb29' into pia-am335x-e2-dev

* commit '8b5b7bc268f3c0b0548ad911395242ab375ffb29':
  pia-am335x: fix DDR initialization for piA-AM335x...
  pia-am335x-eb-tft: enable backup battery charger
  pia-am335x-eb-tft: add board type check for EB_TFT

Conflicts:
	arch/arm/cpu/armv7/am33xx/board.c