Dont build x11 sample with MinGW.

win32/test/GNUmakefile

@@ -26,7 +26,8 @@ endif
 LINK_STATIC = 1
 
 # Edit the vars below to change target settings.
-TARGETS	= $(patsubst ../../example/%.c, %.exe, $(wildcard ../../example/*.c))
+SAMPLES	= ../../example
+TARGETS := $(filter-out x11.exe,$(patsubst $(SAMPLES)/%.c,%.exe,$(strip $(wildcard $(SAMPLES)/*.c))))
 VERSION	= $(LIBSSH2_VERSION)
 COPYR   = (c) $(LIBSSH2_COPYRIGHT_STR)
 WWWURL	= http://www.libssh2.org/