coresight: clear pwrup just after clearing pwrdwn

Having both both ETMPDCR[3] set and ETMCR[0] cleared causes
pre-mature resumes from suspend power collapse. For now, clear
pwrup (ETMPDCR[3]) right after clearing pwrdwn (ETMCR[0]) to
avoid pre-mature resume from suspend power collapse.

Change-Id: I4b951ecc672d42aa9ea1feb7a5f999d24698405e
Signed-off-by: Pratik Patel <pratikp@codeaurora.org>