The Nexus 5 has a vibrator connected to the clock output of GP1_CLK
which we can use with the clk-pwm driver, then we can use that pwm with
pwm-vibrator to get haptics functionality.

This patch is based on Brian Masney's previous patch with clk-vibrator.
Signed-off-by: Luca Weiss <luca@z3ntu.xyz>
Reviewed-by: Konrad Dybcio <konrad.dybcio@linaro.org>
Reviewed-by: Caleb Connolly <caleb.connolly@linaro.org>
Reviewed-by: Brian Masney <bmasney@redhat.com>
Signed-off-by: Bjorn Andersson <andersson@kernel.org>
Link: https://lore.kernel.org/r/20230427-hammerhead-vibra-v1-4-e87eeb94da51@z3ntu.xyz