pinctrl: qcom: Modify MSM_PULL_MASK to accurately represent PULL bits
MSM_PULL_MASK currently spans bits [2:0], but the GPIO_PULL field in the
GPIO_CFG register only occupies bits [1:0]. Bit 2 belongs to
FUNC_SEL.
MSM_PULL_MASK is used to isolate the GPIO_PULL bits before writing the
pull configuration (PULL_DOWN: 0x1, PULL_UP: 0x3) to the GPIO_CFG
register. Narrow it to bits [1:0] to prevent unintended modification of
the FUNC_SEL field.
This causes no functional change since the driver currently does not
modify the FUNC_SEL bit, but align the mask with hardware configuration
nonetheless.