build: rename LOCAL_32BIT_ONLY to LOCAL_32_BIT_ONLY

Rename for consistency with TARGET_IS_64_BIT.

Change-Id: I824dcaed0c1e88b8246bcffb21ab3f1772175926
diff --git a/core/clear_vars.mk b/core/clear_vars.mk
index 32e1de6..f884b19 100644
--- a/core/clear_vars.mk
+++ b/core/clear_vars.mk
@@ -143,7 +143,7 @@
 LOCAL_HAL_STATIC_LIBRARIES:=
 LOCAL_NO_SYNTAX_CHECK:=
 LOCAL_NO_STATIC_ANALYZER:=
-LOCAL_32BIT_ONLY:= # '',true
+LOCAL_32_BIT_ONLY:= # '',true
 LOCAL_NO_2ND_ARCH:= # '',true
 
 # arch specific variables