MIPS: JZ4770: GCW0: Minimize board header

I removed all the parts that are no longer in use, so it is clearer
what still need to be done to get rid of it altogether.
fb: JZ4770: Move headers to driver directory
mmc: JZ4770: Move platform data header
MIPS: JZ4770: GCW0: Include mmc platform data from new location
misc: JZ4770 VPU: Removed unused include
i2c: JZ4770: Move platform data header
MIPS: JZ4770: Remove old I2C header
MIPS: JZ4770: GCW0: Include I2C platform data from new location