target: apq8084: Move boot device detection to common code

Boot device detection is common to targets apq8084,msm8994 and upcoming
targets. So we can make the code common instead of having target
specific changes.

CRs-Fixed: 612217
Change-Id: Iada886e55590c9fe97a72847b42839e52e2e0c52
diff --git a/project/apq8084.mk b/project/apq8084.mk
index 2905eff..250d120 100644
--- a/project/apq8084.mk
+++ b/project/apq8084.mk
@@ -11,6 +11,7 @@
 ENABLE_SDHCI_SUPPORT := 1
 ENABLE_UFS_SUPPORT   := 1
 ENABLE_USB30_SUPPORT := 1
+ENABLE_BOOT_CONFIG_SUPPORT := 1
 
 #DEFINES += WITH_DEBUG_DCC=1
 DEFINES += WITH_DEBUG_UART=1