checksrc/makefile.am: use $top_srcdir to find source files

... to properly support out of source tree builds.

docs/examples/Makefile.am

@@ -63,4 +63,4 @@ include Makefile.inc
 all: $(check_PROGRAMS)
 
 checksrc:
-	@@PERL@ $(top_srcdir)/lib/checksrc.pl -D$(top_srcdir)/docs/examples *.c
+	@PERL@ $(top_srcdir)/lib/checksrc.pl $(top_srcdir)/docs/examples/*.c

lib/Makefile.am

@@ -146,7 +146,8 @@ libcurl_la_SOURCES = $(CSOURCES) $(HHEADERS)
 libcurlu_la_SOURCES = $(CSOURCES) $(HHEADERS)
 
 checksrc:
-	@@PERL@ $(top_srcdir)/lib/checksrc.pl -D$(top_srcdir)/lib -Wcurl_config.h *.[ch] vauth/*.[ch] vtls/*.[ch]
+	@PERL@ $(top_srcdir)/lib/checksrc.pl -W$(top_srcdir)/lib/curl_config.h \
+	$(top_srcdir)/lib/*.[ch] $(top_srcdir)/lib/vauth/*.[ch] $(top_srcdir)/lib/vtls/*.[ch]
 
 if CURLDEBUG
 # for debug builds, we scan the sources on all regular make invokes

src/Makefile.am

@@ -130,7 +130,7 @@ endif
 # ignore tool_hugehelp.c since it is generated source code and it plays
 # by slightly different rules!
 checksrc:
-	@@PERL@ $(top_srcdir)/lib/checksrc.pl -D$(top_srcdir)/src -Wtool_hugehelp.c *.[ch]
+	@PERL@ $(top_srcdir)/lib/checksrc.pl -W$(top_srcdir)/src/tool_hugehelp.c $(top_srcdir)/src/*.[ch]
 
 if CURLDEBUG
 # for debug builds, we scan the sources on all regular make invokes

tests/libtest/Makefile.am

@@ -117,4 +117,4 @@ libhostname_la_LIBADD =
 libhostname_la_DEPENDENCIES =
 
 checksrc:
-	@@PERL@ $(top_srcdir)/lib/checksrc.pl $(top_srcdir)/tests/libtest/*.c
+	@PERL@ $(top_srcdir)/lib/checksrc.pl $(top_srcdir)/tests/libtest/*.c

tests/server/Makefile.am

@@ -63,4 +63,4 @@ include Makefile.inc
 EXTRA_DIST = base64.pl Makefile.inc CMakeLists.txt
 
 checksrc:
-	@@PERL@ $(top_srcdir)/lib/checksrc.pl $(top_srcdir)/tests/libtest/*.c
+	@PERL@ $(top_srcdir)/lib/checksrc.pl $(top_srcdir)/tests/libtest/*.c

tests/unit/Makefile.am

@@ -72,7 +72,7 @@ AM_CPPFLAGS += -DCURL_STATICLIB -DUNITTESTS
 include Makefile.inc
 
 checksrc:
-	@@PERL@ $(top_srcdir)/lib/checksrc.pl $(top_srcdir)/tests/unit/*.c
+	@PERL@ $(top_srcdir)/lib/checksrc.pl $(top_srcdir)/tests/unit/*.c
 
 if BUILD_UNITTESTS
 noinst_PROGRAMS = $(UNITPROGS)