msm: ext_display: increase timeout value to 5 seconds

For targets not having a HAL component, a userspace testapp has
to be manually run to trigger a frame update which will in-turn
trigger the unblank sequence.
This testapp needs to be run within the specified timeout value
of the hpd_comp. Current value of 2 seconds is not enough and
causes false errors and subsequent failures.

Increase timeout value to 5 seconds to avoid false timeouts for
no framework cases.

CRs-Fixed: 1115561
Change-Id: I14f64f781c19268510128f5fa819e7fd0d33c78b
Signed-off-by: Manoj Kumar AVM <manojavm@codeaurora.org>