msm: ipa: Add IOCTL support to get ep_pair info

For QMI dpm port to open, control manager needs
to know about usb/mhi ep details corresponding to
RMNET and RMNET_CV2X tethering.
IPA driver has all endpoint info at one place.
So provide IOCTL interface to get ep_pair info.

Change-Id: Ia5ec0df955ef7794ca992129dab538f65af36211
Signed-off-by: Mohammed Javid <mjavid@codeaurora.org>