arm: exynos: Squash bogus warnings in pinmux

Squash these warnings in pinmux.c found with GCC 4.8:

/arch/arm/cpu/armv7/exynos/pinmux.c: In function 'exynos_pinmux_config':
/arch/arm/cpu/armv7/exynos/pinmux.c:687:28: warning: 'count' may be used uninitialized in this function [-Wmaybe-uninitialized]
  for (i = start; i < start + count; i++) {
                            ^
/arch/arm/cpu/armv7/exynos/pinmux.c:663:16: note: 'count' was declared here
  int i, start, count;
                ^
/arch/arm/cpu/armv7/exynos/pinmux.c:687:28: warning: 'start' may be used uninitialized in this function [-Wmaybe-uninitialized]
  for (i = start; i < start + count; i++) {
                            ^
/arch/arm/cpu/armv7/exynos/pinmux.c:663:9: note: 'start' was declared here
  int i, start, count;
         ^
/arch/arm/cpu/armv7/exynos/pinmux.c:689:19: warning: 'bank' may be used uninitialized in this function [-Wmaybe-uninitialized]
   s5p_gpio_cfg_pin(bank, i, GPIO_FUNC(0x2));
                   ^
/arch/arm/cpu/armv7/exynos/pinmux.c:662:24: note: 'bank' was declared here
  struct s5p_gpio_bank *bank;
                        ^
/arch/arm/cpu/armv7/exynos/pinmux.c: In function 'exynos_pinmux_config':
/arch/arm/cpu/armv7/exynos/pinmux.c:687:28: warning: 'count' may be used uninitialized in this function [-Wmaybe-uninitialized]
  for (i = start; i < start + count; i++) {
                            ^
/arch/arm/cpu/armv7/exynos/pinmux.c:663:16: note: 'count' was declared here
  int i, start, count;
                ^
/arch/arm/cpu/armv7/exynos/pinmux.c:687:28: warning: 'start' may be used uninitialized in this function [-Wmaybe-uninitialized]
  for (i = start; i < start + count; i++) {
                            ^
/arch/arm/cpu/armv7/exynos/pinmux.c:663:9: note: 'start' was declared here
  int i, start, count;
         ^
/arch/arm/cpu/armv7/exynos/pinmux.c:689:19: warning: 'bank' may be used uninitialized in this function [-Wmaybe-uninitialized]
   s5p_gpio_cfg_pin(bank, i, GPIO_FUNC(0x2));
                   ^
/arch/arm/cpu/armv7/exynos/pinmux.c:662:24: note: 'bank' was declared here
  struct s5p_gpio_bank *bank;
                        ^

Note that the warning is bogus, the function can never be called with invalid
'peripheral' argument. GCC just cannot analyze this.

Signed-off-by: Marek Vasut <marex@denx.de>
Cc: Naveen Krishna Chatradhi <ch.naveen@samsung.com>
Cc: Akshay Saraswat <akshay.s@samsung.com>
Cc: Simon Glass <sjg@chromium.org>
Cc: Tom Rini <trini@ti.com>
Acked-by: Simon Glass <sjg@chromium.org>
Acked-by: Rajeshwari S Shinde <rajeshwari.s@samsung.com>
Signed-off-by: Lukasz Majewski <l.majewski@samsung.com>
Signed-off-by: Minkyu Kang <mk7.kang@samsung.com>