hwspinlock: qcom: Correct msb in regmap_field

msb of the regmap_field was mistakenly given the value 32, to set all bits
in the regmap update mask; although incorrect this worked until 921cc294,
where the mask calculation was corrected.

Signed-off-by: Bjorn Andersson <bjorn.andersson@sonymobile.com>
Signed-off-by: Ohad Ben-Cohen <ohad@wizery.com>