Blackfin: gpio: optimize free path a little

When we aren't doing resource tracking, the gpio_free() function is a
stub that simply returns, so pull this logic up a level and make it an
inline stub in the header.  Now we don't have to waste time at any of
the call sites.

Signed-off-by: Mike Frysinger <vapier@gentoo.org>
diff --git a/arch/blackfin/include/asm/gpio.h b/arch/blackfin/include/asm/gpio.h
index 9c0e5d1..224688f 100644
--- a/arch/blackfin/include/asm/gpio.h
+++ b/arch/blackfin/include/asm/gpio.h
@@ -142,8 +142,10 @@
 
 #ifdef CONFIG_BFIN_GPIO_TRACK
 void bfin_gpio_labels(void);
+void bfin_gpio_free(unsigned gpio);
 #else
 #define bfin_gpio_labels()
+#define bfin_gpio_free(gpio)
 #define bfin_gpio_request(gpio, label) bfin_gpio_request(gpio)
 #define bfin_special_gpio_request(gpio, label) bfin_special_gpio_request(gpio)
 #endif
@@ -154,7 +156,6 @@
 #endif
 
 int bfin_gpio_request(unsigned gpio, const char *label);
-void bfin_gpio_free(unsigned gpio);
 int bfin_gpio_direction_input(unsigned gpio);
 int bfin_gpio_direction_output(unsigned gpio, int value);
 int bfin_gpio_get_value(unsigned gpio);