ARM: dts: msm: add PM7250B and SMB1394 to sdxlemur-mtp-mbb-emmc boards

sdxlemur-mtp-mbb-emmc boards use PM7250B and SMB1394 similar to
sdxlemur-mtp-mbb boards. However, sdxlemur-mtp-mbb-emmc.dtsi has
sdxlemur-pmic-overlay.dtsi which only adds PMK8350 and PMX65.

Add pm7250b.dtsi and smb1394.dtsi to sdxlemur-mtp-mbb-emmc.dtsi
so that sdxlemur-mtp-mbb-emmc boards can now use USB VBUS
detection from PM7250B charger peripheral instead of VBUS_DET
peripheral from PMX65.

Change-Id: I72a63eb3f6b3f2b8c779e40593da9b7499a69478