Explicitly mark main() as public in executables to avoid an HP-UX

ld warning.

compat/mksiglist.c

@@ -32,6 +32,8 @@
 
 #include "missing.h"
 
+__dso_public int main(int argc, char *argv[]);
+
 int
 main(int argc, char *argv[])
 {

compat/mksigname.c

@@ -32,6 +32,8 @@
 
 #include "missing.h"
 
+__dso_public int main(int argc, char *argv[]);
+
 int
 main(int argc, char *argv[])
 {

compat/regress/fnmatch/fnm_test.c

@@ -20,6 +20,8 @@
 # include "compat/fnmatch.h"
 #endif
 
+__dso_public int main(int argc, char *argv[]);
+
 int
 main(int argc, char *argv[])
 {

compat/regress/glob/globtest.c

@@ -33,6 +33,7 @@ struct gl_entry {
 };
 
 int test_glob(struct gl_entry *);
+__dso_public int main(int argc, char *argv[]);
 
 int
 main(int argc, char **argv)