clk: at91: sam9x60: remove atmel,osc-bypass support

clk: at91: sam9x60: remove atmel,osc-bypass support

The sam9x60 doesn't have the MOSCXTBY bit to enable the crystal oscillator
bypass.

Fixes: 0847deaafccc ("clk: at91: add sam9x60 pmc driver")
Reported-by: Claudiu Beznea <claudiu.beznea@microchip.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Link: https://lore.kernel.org/r/20201202125816.168618-1-alexandre.belloni@bootlin.com
Reviewed-by: Claudiu Beznea <claudiu.beznea@microchip.com>
Tested-by: Claudiu Beznea <claudiu.beznea@microchip.com>
Signed-off-by: Stephen Boyd <sboyd@kernel.org>