ARM: pxa: fix build issue on stargate2

arch/arm/mach-pxa/stargate2.c:155:3: error: unknown field ‘dev’
specified in initializer
arch/arm/mach-pxa/stargate2.c:155:3: warning: initialization from
incompatible pointer type [enabled by default]
arch/arm/mach-pxa/stargate2.c:155:3: warning: (near initialization for
‘stargate2_sensor_3_con[0].dev_name’) [enabled by default]
make[1]: *** [arch/arm/mach-pxa/stargate2.o] Error 1
make: *** [arch/arm/mach-pxa] Error 2

It's caused by 'dev' field removed from struct
regulator_consumer_supply.

Signed-off-by: Haojian Zhuang <haojian.zhuang@gmail.com>