Makefile: we should use COMPAT instead of NO_COMPAT.

That's what configure defines.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>

.travis.yml

@@ -10,7 +10,7 @@ env:
   - VALGRIND=0 ARCH=32 DEVELOPER=1 COMPILER=gcc TEST_GROUP=1 TEST_GROUP_COUNT=2 SOURCE_CHECK_ONLY=false
   - VALGRIND=0 ARCH=32 DEVELOPER=1 COMPILER=gcc TEST_GROUP=2 TEST_GROUP_COUNT=2 SOURCE_CHECK_ONLY=false
   - VALGRIND=0 ARCH=64 DEVELOPER=1 COMPILER=gcc SOURCE_CHECK_ONLY=false
-  - VALGRIND=0 ARCH=64 DEVELOPER=0 COMPILER=gcc NO_COMPAT=1 SOURCE_CHECK_ONLY=false
+  - VALGRIND=0 ARCH=64 DEVELOPER=0 COMPILER=gcc COMPAT=0 SOURCE_CHECK_ONLY=false
   - VALGRIND=1 ARCH=64 DEVELOPER=0 COMPILER=gcc TEST_GROUP=1 TEST_GROUP_COUNT=3 SOURCE_CHECK_ONLY=false
   - VALGRIND=1 ARCH=64 DEVELOPER=0 COMPILER=gcc TEST_GROUP=2 TEST_GROUP_COUNT=3 SOURCE_CHECK_ONLY=false
   - VALGRIND=1 ARCH=64 DEVELOPER=0 COMPILER=gcc TEST_GROUP=3 TEST_GROUP_COUNT=3 SOURCE_CHECK_ONLY=false

Makefile

@@ -31,7 +31,7 @@ PIE_CFLAGS=-fPIE -fPIC
 PIE_LDFLAGS=-pie
 endif
 
-ifneq ($(NO_COMPAT),1)
+ifeq ($(COMPAT),1)
 # We support compatibility with pre-0.6.
 COMPAT_CFLAGS=-DCOMPAT_V052=1
 endif