Replace is-vendor-board-platform with is-vendor-board-qcom.

Bug: 201477826
Test: treehugger

This change has been generated by the following script:

```
#! /bin/bash
declare -r files="$(grep -rlP '^[^#]*call +is-vendor-board-platform' --include '*.mk')"
[[ -z "$files" ]] || sed -i -r -f <(cat <<"EOF"
s/ifeq \(\$\(call is-vendor-board-platform,QCOM\),true\)/ifneq (,$(call is-vendor-board-qcom))/
s/ifneq \(\$\(call is-vendor-board-platform,QCOM\),true\)/ifeq (,$(call is-vendor-board-qcom))/
EOF
) $files
```

Change-Id: Ic99bf3e5395ebdcd468b5d22921b5559bfdc5b03
diff --git a/Android.mk b/Android.mk
index bdae8dc..7339d6c 100644
--- a/Android.mk
+++ b/Android.mk
@@ -9,7 +9,7 @@
 
 display-hals += gralloc
 
-ifeq ($(call is-vendor-board-platform,QCOM),true)
+ifneq (,$(call is-vendor-board-qcom))
     include $(call all-named-subdir-makefiles,$(display-hals))
 else
 ifneq ($(filter ms% msm% apq%,$(TARGET_BOARD_PLATFORM)),)