misc: qpnp-misc: change the initcall level for qpnp-misc driver

Change the initcall level of qpnp-misc driver from module_init()
to subsys_initcall() so that the misc devices can be available
earlier. This helps the clients to access the registers under
misc peripheral sooner without a probe deferral.

Change-Id: Ie5df2cb9cf6842c59ec6f00ac9123994111f207b
Signed-off-by: Subbaraman Narayanamurthy <subbaram@codeaurora.org>