Makefile: fix check framework compilation flags

Makefile

@@ -6,7 +6,8 @@
 
 CFLAGS = -g -Wall -Wextra -Werror -std=c99
 CFLAGS += -D_POSIX_C_SOURCE=199309L -D_BSD_SOURCE -D_DEFAULT_SOURCE -D_DARWIN_C_SOURCE
-LDLIBS = -lcheck
+CFLAGS += $(shell pkg-config --cflags check)
+LDLIBS += $(shell pkg-config --libs check)
 
 all: scan-build test example
 	@echo "+++ All good."""