This commit fixes the name for the GMAC clock to gmac_clkin, as this is
the name of the clock provided by the rk3328-clk driver.
Without this commit, the GMAC will not work in TX direction.
Suggested-by: Tobias Waldvogel <tobias.waldvogel@gmail.com>
Signed-off-by: David Bauer <mail@david-bauer.net>