Convert CONFIG_RESET_PHY_R to Kconfig

This converts the following to Kconfig:
   CONFIG_RESET_PHY_R

Cc: Ramon Fried <rfried.dev@gmail.com>
Signed-off-by: Tom Rini <trini@konsulko.com>
diff --git a/common/Kconfig b/common/Kconfig
index 24c83f0..383eb4d 100644
--- a/common/Kconfig
+++ b/common/Kconfig
@@ -611,6 +611,12 @@
 	  case of DM PCI-based Ethernet devices, which will not be detected
 	  without having the enumeration performed earlier.
 
+config RESET_PHY_R
+	bool "Reset ethernet PHY during init"
+	help
+	  Implement reset_phy() in board code if required to reset the ethernet
+	  PHY.
+
 endmenu
 
 endmenu		# Init options