ARM: dts: qcom: msm8974pro-castor: Remove camera button definitions

ARM: dts: qcom: msm8974pro-castor: Remove camera button definitions

>From what I can tell, the camera buttons are not part of Z2 Tablet
hardware even though other devices based on 'shinano' do have them.

Fixes: ab80661883de ("ARM: dts: qcom: msm8974: Add Sony Xperia Z2 Tablet")
Signed-off-by: Luca Weiss <luca@z3ntu.xyz>
Reviewed-by: Konrad Dybcio <konrad.dybcio@linaro.org>
Link: https://lore.kernel.org/r/20240306-castor-changes-v1-3-2286eaf85fff@z3ntu.xyz
Signed-off-by: Bjorn Andersson <andersson@kernel.org>