drm/msm/dsi_phy_28nm_8960: Use stack memory for temporary clock names

The clock names formatted into the hw_clk's init structure are only used
for the duration of the registration function where they are kstrdup'ed,
making it unnecessary to keep the allocations alive for the duration of
the device (through devm).

Just like the other DSI PHY PLL clock trees, use a stack-local char
array and save on memory outside of the pll_28nm_register function.

Signed-off-by: Marijn Suijten <marijn.suijten@somainline.org>
Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Patchwork: https://patchwork.freedesktop.org/patch/491917/
Link: https://lore.kernel.org/r/20220629225331.357308-6-marijn.suijten@somainline.org


Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Signed-off-by: Rob Clark <robdclark@chromium.org>