ARM: dts: msm: remove unwanted IPA features on sdxpoorwills

Scatter-gather is not supported on sdxpoorwills. Also platform
type needs to be set to LE when updating to modem. Make changes
to remove sg and ipa-loaduC entries.

Change-Id: I4d662e3e7bf90bb2a57fa567c2caa956405ce380
Acked-by: Chaitanya Pratapa <cpratapa@qti.qualcomm.com>
Signed-off-by: Mohammed Javid <mjavid@codeaurora.org>