memshare: Fix parameters to collect ramdump

This patch defines condition for collecting ramdump
only when ramdump collection is enabled, modem is crashed
and memshare is notified of SUBSYS_RAMDUMP_NOTIFICATION.

CRs-Fixed: 1114015
Change-Id: I7e3ca0794980fd21cc0a5d890df4aeadfd5fbbbb
Signed-off-by: Manoj Prabhu B <bmanoj@codeaurora.org>