add ofw api to of net,driver writer can use this api get phy modes or get mac address

Author: zhuzhuzhus

components/drivers/phy/SConscript

@@ -2,7 +2,9 @@ from building import *
 
 cwd     = GetCurrentDir()
 src = Glob('*.c')
-CPPPATH = [cwd + '/../include']
+if GetDepend('RT_USING_OFW') == False:
+    SrcRemove(src, ['ofw.c'])
+CPPPATH = [cwd,cwd + '/../include']
 group = DefineGroup('DeviceDrivers', src, depend = ['RT_USING_PHY'], CPPPATH = CPPPATH)
 
 Return('group')