[PATCH] build: honor results obtained by pkg-config libinput

[Jan Engelhardt]

The error was:
src/libinput-seat.c:30:22: fatal error: libinput.h: No such file or directory
---
 Makefile.am | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/Makefile.am b/Makefile.am
index b2d6893..7f3e5d3 100644
--- a/Makefile.am
+++ b/Makefile.am
@@ -34,7 +34,8 @@ AM_CPPFLAGS = 					\
 	-DDATADIR='"$(datadir)"'		\
 	-DMODULEDIR='"$(moduledir)"'		\
 	-DLIBEXECDIR='"$(libexecdir)"'		\
-	-DBINDIR='"$(bindir)"'
+	-DBINDIR='"$(bindir)"' \
+	$(LIBINPUT_BACKEND_CFLAGS)
 
 CLEANFILES = weston.ini $(BUILT_SOURCES)
 
-- 
2.0.0