MIPS: TXx9: Make spi_eeprom.c more generic

Helper routines in txx9/rbtx4938/spi_eeprom.c is not TX4938 specific.
Move it to txx9/generic/ directory and make it works with SPI bus
number other than 0.

Signed-off-by: Atsushi Nemoto <anemo@mba.ocn.ne.jp>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

 create mode 100644 arch/mips/txx9/generic/spi_eeprom.c
 delete mode 100644 arch/mips/txx9/rbtx4938/spi_eeprom.c
5 files changed