[ARM] fix nwflash.c: 6ee8928d

drivers/char/nwflash.c: In function 'flash_read':
drivers/char/nwflash.c:129: error: 'p' undeclared (first use in this function)
drivers/char/nwflash.c:129: error: (Each undeclared identifier is reported only once
drivers/char/nwflash.c:129: error: for each function it appears in.)
drivers/char/nwflash.c:129: error: 'count' undeclared (first use in this function)
drivers/char/nwflash.c:136: warning: passing argument 4 of 'simple_read_from_buffer' discards qualifiers from pointer target type

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>