ARM: dts: msm: Remove "qcom,throttle-pwrlevel" from 525MHz GPU clk plan

"qcom,throttle-pwrlevel" property is needed only when LM is required
for any corner in freq plan. As for 525MHz plan, LM is not required
remove this property to avoid enabling LM for 525MHz frequency.

Change-Id: Ib939581e8707d0477661427234f82a530744a054