staging: fbtft: sh1106: use new macro FBTFT_REGISTER_SPI_DRIVER

Make fb_sh1106 the first user of new macro FBTFT_REGISTER_SPI_DRIVER.
In addition the MODULE_ALIASes can be removed. Module auto-loading
was successfully tested with a SH1106-based OLED module connected
to an Odroid C2.

Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Link: https://lore.kernel.org/r/65516be1-9588-af00-cf4f-053e20af9b45@gmail.com


Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>