Use SPI library for Teensy LC

With this commit no direct register access to SPI hardware should be done anymore for Teensy LC. This is done in the same way as for Teensy 4. Additionally the USE_TEENSY4_SPI define was renamed to USE_SPI_LIB as it is now used for not only Teensy 4.

Fix wrong comment

Updated fir T40=-Beta2 and Builtin SD Card define

check alignment for DMA buffers

Ported to T4b1

-added T4 aware functions
-chenged transfer from polling to internal DMA (blocking mode)

07_feb-2019

T4 support

add 256MHz

enable required Pullups in SDHC_ReleaseGPIO(void)

Fix writes/reads >=64KB

(attention, untested)