Revert "msm: mdss: enable pll regulator during phy on sequence"

This reverts commit 32461b78 ("
msm: mdss: enable pll regulator during phy on sequence").This commit
is causing suspend/resume failure, revert it until issue is root caused.

Change-Id: I76ff5affef32ca7dead433b49b636045a13b1dc5
Signed-off-by: Vishnuvardhan Prodduturi <vproddut@codeaurora.org>