[DRIVERS] gpio: Get ARCH_NR_GPIOS value using config option

This patch adds menuconfig option CONFIG_ARCH_NR_GPIO to set value of
system's max number of GPIO chips.
Default is 1024.

Signed-off-by: Pranavkumar Sawargaonkar <pranav.sawargaonkar@gmail.com>
[DRIVERS] pinctrl: Adding new sunxi pinctrl driver.

This driver has been ported from linux's pinctrl-sunxi driver.
This is compilable version but not fully tested.
Will add subsequent fixme patches for bugs found during further testing.

Signed-off-by: Pranavkumar Sawargaonkar <pranav.sawargaonkar@gmail.com>
[CORE] vmm_devtree: Fixing vmm_devtree_next_string() and other misc.

This patch fixes:

vmm_devtree_next_string() function:
This function had a issue with returning wrong non null value even if
last string is already read.
This used to affect behavior of_property_for_each_string()

Fixes vmm_devtree_regsize(), vmm_devtree_regaddr() functions.

Signed-off-by: Pranavkumar Sawargaonkar <pranav.sawargaonkar@gmail.com>
[DRIVERS] net: pinctrl: Minor fix in few debug prints

This patch adds __func__ in few debugs prints in these drivers.

Signed-off-by: Pranavkumar Sawargaonkar <pranav.sawargaonkar@gmail.com>