Fix warning about missing terminating ' character

Bug: 302724232
Test: build binder with GCC
Change-Id: I5bb7cff8999f6fb6f2411eb8697a79c979d12103
diff --git a/libs/binder/Stability.cpp b/libs/binder/Stability.cpp
index 2d05fb2..c432b3a 100644
--- a/libs/binder/Stability.cpp
+++ b/libs/binder/Stability.cpp
@@ -75,7 +75,7 @@
 
 Stability::Level Stability::getLocalLevel() {
 #ifdef __ANDROID_APEX__
-#error APEX can't use libbinder (must use libbinder_ndk)
+#error "APEX can't use libbinder (must use libbinder_ndk)"
 #endif
 
 #ifdef __ANDROID_VNDK__