DaVinci EMAC: declare function for all DA8xx CPUs

The function davinci_emac_mii_mode_sel() is defined in
board/davinci/common/misc.c for any DA8xx CPU which has
CONFIG_DRIVER_TI_EMAC enabled. However, the prototype was only being
declared in <include/asm/arch/davinci_misc.h> for the DA850 EVM board.
This patch declares it for all DA8xx CPUs where CONFIG_DRIVER_TI_EMAC
is enabled.
Signed-off-by: NLaurence Withers <lwithers@guralp.com>
Signed-off-by: NSandeep Paulraj <s-paulraj@ti.com>

arch/arm/include/asm/arch-davinci/davinci_misc.h

@@ -57,7 +57,7 @@ void davinci_sync_env_enetaddr(uint8_t *rom_enetaddr);
 int davinci_configure_pin_mux(const struct pinmux_config *pins, int n_pins);
 int davinci_configure_pin_mux_items(const struct pinmux_resource *item,
 				    int n_items);
-#if defined(CONFIG_DRIVER_TI_EMAC) && defined(CONFIG_MACH_DAVINCI_DA850_EVM)
+#if defined(CONFIG_DRIVER_TI_EMAC) && defined(CONFIG_SOC_DA8XX)
 void davinci_emac_mii_mode_sel(int mode_sel);
 #endif
 #if defined(CONFIG_SOC_DA8XX)