MIPS: JZ4750D: Remove some unused /proc/jz interfaces

  Removed:
    /proc/jz/udc, /proc/jz/mmc, /proc/jz/ipu and /proc/jz/imem

  Left for debugging:
    /proc/jz/emc, /proc/jz/pmc and /proc/jz/cgm
MIPS: JZ4750D: Remove disabling gpios from pm.c
MIPS: JZ4750D: Remove i2c.c from platform code