autotools: fixed building of check_parser

By default libtool choose dynamic library for linking. Since non-public
API is hidden in libstrophe.so check_parser has been broken. As solution
libtool takes static libstophe.a now.

Author: pasis

Makefile.am

@@ -63,3 +63,4 @@ tests_check_parser_SOURCES = tests/check_parser.c tests/test.h
 tests_check_parser_CFLAGS = @check_CFLAGS@ $(PARSER_CFLAGS) $(STROPHE_FLAGS) \
 	-I$(top_srcdir)/src
 tests_check_parser_LDADD = @check_LIBS@ $(STROPHE_LIBS)
+tests_check_parser_LDFLAGS = -static