net: phy: at803x: don't inline helpers

Some helpers were declared with the "inline" function specifier.
It is preferable to let the compiler pick the right optimizations,
so drop the specifier for at803x_disable_rx_delay() and
at803x_disable_tx_delay()

Reviewed-by: Niklas Cassel <niklas.cassel@linaro.org>
Tested-by: Peter Ujfalusi <peter.ujflausi@ti.com>
Reviewed-by: Marc Gonzalez <marc.w.gonzalez@free.fr>
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>