pinctrl: qcom: pinctrl-msm: Complete 'struct msm_pinctrl' documentation

Add missing descriptions for attributes and fix 1 formatting issue.

Fixes the following W=1 kernel build warning(s):

 drivers/pinctrl/qcom/pinctrl-msm.c:75: warning: Function parameter or member 'desc' not described in 'msm_pinctrl'
 drivers/pinctrl/qcom/pinctrl-msm.c:75: warning: Function parameter or member 'irq_chip' not described in 'msm_pinctrl'
 drivers/pinctrl/qcom/pinctrl-msm.c:75: warning: Function parameter or member 'intr_target_use_scm' not described in 'msm_pinctrl'
 drivers/pinctrl/qcom/pinctrl-msm.c:75: warning: Function parameter or member 'soc' not described in 'msm_pinctrl'
 drivers/pinctrl/qcom/pinctrl-msm.c:75: warning: Function parameter or member 'phys_base' not described in 'msm_pinctrl'

Signed-off-by: Lee Jones <lee.jones@linaro.org>
Cc: Bjorn Andersson <bjorn.andersson@linaro.org>
Cc: Andy Gross <agross@kernel.org>
Cc: linux-arm-msm@vger.kernel.org
Link: https://lore.kernel.org/r/20200713144930.1034632-6-lee.jones@linaro.org


Signed-off-by: Linus Walleij <linus.walleij@linaro.org>