Don't touch rx_ena, tx_ena in EPORT_UMAC_CMD reg

rx_ena and tx_ena are controlled by MoCAOS_EnableDataIf() in mocad.
Don't interfere with it as it might cause MoCA assertions.

Change-Id: I69be8f01cdfbce9813f37b963222234594902381
diff --git a/bmoca-6802.c b/bmoca-6802.c
index 22284ac..5714cad 100644
--- a/bmoca-6802.c
+++ b/bmoca-6802.c
@@ -322,7 +322,6 @@
 	MOCA_WR(0x10800000, 0x03);       // EMUX_CNTRL
 	MOCA_WR(0x1080000c, 0x11);       // RGMII_0_CNTRL
 	MOCA_WR(0x10800014, 0xc0);       // RGMII_0_RX_CLK_DELAY_CNTRL
-	MOCA_WR(0x10800808, 0x010000db); // UMAC_CMD
 
 	MOCA_WR(0x104040a4, 0x01);       // GENERAL_CTRL_NO_SCAN_0
 	MOCA_WR(0x10404100, 0x11110011); // PIN_MUX_CTRL_0