uboot-imx

MLK-21842-3 imx8mq_evk: Fix ENET GPR selection bit

Only the GPR0 bit[13] is used as GPR_ENET1_TX_CLK_SEL, bit[17] is reserved
on imx8mq. So we don't need to clear bit[17].

Add the definition of bit[13] in register file.
Also fix the size of gpr array, should be 48 not 47.

Signed-off-by: Ye Li <ye.li@nxp.com>