mx6: clock: Pass the frequency as argument of enable_fec_anatop_clock()

Provide an argument to enable_fec_anatop_clock() to specify the clock frequency
that will be generated.

No changes are made to mx6slevk, which uses the default 50MHz fec clock.

Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com>
Acked-by: Stefano Babic <sbabic@denx.de>
diff --git a/board/freescale/mx6slevk/mx6slevk.c b/board/freescale/mx6slevk/mx6slevk.c
index dfc5746..c496254 100644
--- a/board/freescale/mx6slevk/mx6slevk.c
+++ b/board/freescale/mx6slevk/mx6slevk.c
@@ -120,7 +120,7 @@
 	/* clear gpr1[14], gpr1[18:17] to select anatop clock */
 	clrsetbits_le32(&iomuxc_regs->gpr[1], IOMUX_GPR1_FEC_MASK, 0);
 
-	ret = enable_fec_anatop_clock();
+	ret = enable_fec_anatop_clock(ENET_50MHz);
 	if (ret)
 		return ret;