ARM: tegra: defconfig updates

New options enabled:
* BRCMFMAC: wlan driver, enable as module.
* MTD, MTD_CHAR, MTD_M25P80, SPI_TEGRA20_SLINK, CONFIG_SPI_TEGRA20_SFLASH
  to enable serial flash on Cardhu and TrimSlice.
* PWM/backlight features for use with tegradrm.
* tegradrm; Tegra's new display driver.
* CMA, so that tegradrm can allocate large buffers.
* SquashFS, which is used as the root filesystem on boards based on
  the Tamonten processor module.

Signed-off-by: Wei Ni <wni@nvidia.com>
Signed-off-by: Laxman Dewangan <ldewangan@nvidia.com>
Signed-off-by: Thierry Reding <thierry.reding@avionic-design.de>
Signed-off-by: Stephen Warren <swarren@nvidia.com>