ARM DaVinci: Changing function names for EMAC driver

DM644x is just one of a series of DaVinci chips that use the EMAC driver.
By replacing all the function names that start with dm644x_* to davinci_*
we make these function more portable. I have tested this change on my EVM.
DM6467 is another DaVinci SOC which uses the EMAC driver and i will
be sending patches that add DaVinci DM6467 support to the list soon.

Signed-off-by: Sandeep Paulraj <s-paulraj@ti.com>
diff --git a/net/eth.c b/net/eth.c
index 4e508a0..c35c57b 100644
--- a/net/eth.c
+++ b/net/eth.c
@@ -599,7 +599,7 @@
 	ns7520_miiphy_initialize(bis);
 #endif
 #if defined(CONFIG_DRIVER_TI_EMAC)
-	dm644x_eth_miiphy_initialize(bis);
+	davinci_eth_miiphy_initialize(bis);
 #endif
 	return 0;
 }