target: msm8974: Add support for 8994 interposer

Add support for 8994 interposer board, this needs disabling display
usb3 support and detect the new subtype for interposer board.

CRs-Fixed: 663154
Change-Id: Ia52243ddcc78df63da5a8da71df3de5546970fef
diff --git a/include/target.h b/include/target.h
index 34798c6..3986a97 100644
--- a/include/target.h
+++ b/include/target.h
@@ -72,5 +72,6 @@
 void target_usb_phy_mux_configure(void);
 target_usb_iface_t * target_usb30_init();
 bool target_is_cdp_qvga();
+uint32_t target_hw_interposer();
 
 #endif