Check for features missing in mingw environment, allowing tools
subdirectory to be cross-built again.

diff --git a/configure.ac b/configure.ac
index 3284c6b..321afae 100644
--- a/configure.ac
+++ b/configure.ac
@@ -1158,6 +1158,7 @@
 	sendmsg \
 	settimeofday \
 	sigaltstack \
+	sigprocmask \
 	snprintf \
 	spawnvp \
 	statfs \
@@ -1244,6 +1245,7 @@
 AC_C_CONST
 AC_C_INLINE
 AC_CHECK_TYPES([mode_t, off_t, pid_t, size_t, ssize_t, long long, fsblkcnt_t, fsfilcnt_t])
+AC_CHECK_TYPES([sigset_t],,,[#include <signal.h>])
 
 AC_CACHE_CHECK([whether linux/input.h is for real],
 	wine_cv_linux_input_h,
@@ -1265,6 +1267,14 @@
                   [Define if we have linux/input.h AND it contains the INPUT event API])
     fi
 
+AC_CACHE_CHECK([for sigaddset],wine_cv_have_sigaddset,
+               AC_TRY_LINK([#include <signal.h>],[sigset_t set; sigaddset(&set,SIGTERM);],
+                           wine_cv_have_sigaddset=yes,wine_cv_have_sigaddset=no))
+if test "$wine_cv_have_sigaddset" = "yes"
+then
+  AC_DEFINE(HAVE_SIGADDSET, 1, [Define if sigaddset is supported])
+fi
+
 
 AC_CACHE_CHECK([whether we can use re-entrant gethostbyname_r Linux style],
    	wine_cv_linux_gethostbyname_r_6,