uboot-imx

mx5 clocks: Fix MXC_FEC_CLK

The FEC clock does not come from PLL1, but from the IPG clock. The previous code
was even inconsistent with itself, returning the IPG clock as expected for
imx_get_fecclk(), but the PLL1 clock for mxc_get_clock(MXC_FEC_CLK).

Signed-off-by: Benoît Thébaudeau <benoit.thebaudeau@advansee.com>
Cc: Stefano Babic <sbabic@denx.de>