msm: lpm_resources: Modify LPM dts parsing

Parse the resource id, type and key for an lpm resource
only if it is an RPM resource. A new field in the dts
identifies if the lpm resource being processed is an RPM
resource or not.

Change-Id: I234a459bcffc5ca51f43e1fa738170559a2e7bfc
Signed-off-by: Girish Mahadevan <girishm@codeaurora.org>