Make autoconf/automake build compatible with msys

Makefile.am

@@ -1,6 +1,6 @@
 # Process this file with automake to create Makefile.in for wxsqlite3 library
 #
-# Copyright (C) 2017-2020 Ulrich Telle <ulrich@telle-online.de>, Vadim Zeitlin <vadim@wxwidgets.org>
+# Copyright (C) 2017-2023 Ulrich Telle <ulrich@telle-online.de>, Vadim Zeitlin <vadim@wxwidgets.org>
 #
 # This file is covered by the same licence as the entire wxSQLite3 package.
 
@@ -27,7 +27,11 @@ AM_CFLAGS   = -I$(top_srcdir)/include -I$(top_srcdir)/src $(WX_CXXFLAGS)
 AM_CXXFLAGS += -DSQLITE_ENABLE_COLUMN_METADATA=1 -DSQLITE_USER_AUTHENTICATION=1
 AM_CFLAGS += -std=c99 -DSQLITE_THREADSAFE=1 -DSQLITE_DQS=0 -DSQLITE_MAX_ATTACHED=10 -DSQLITE_ENABLE_EXPLAIN_COMMENTS=1 -DSQLITE_SOUNDEX=1 -DSQLITE_ENABLE_COLUMN_METADATA=1 -DSQLITE_SECURE_DELETE=1 -DSQLITE_ENABLE_DESERIALIZE=1 -DSQLITE_ENABLE_FTS3=1 -DSQLITE_ENABLE_FTS3_PARENTHESIS=1 -DSQLITE_ENABLE_FTS4=1 -DSQLITE_ENABLE_FTS5=1 -DSQLITE_ENABLE_RTREE=1 -DSQLITE_ENABLE_GEOPOLY=1 -DSQLITE_CORE=1 -DSQLITE_ENABLE_EXTFUNC=1 -DSQLITE_ENABLE_MATH_FUNCTIONS=1 -DSQLITE_ENABLE_CSV=1 -DSQLITE_ENABLE_VSV=1 -DSQLITE_ENABLE_SHA3=1 -DSQLITE_ENABLE_CARRAY=1 -DSQLITE_ENABLE_FILEIO=1 -DSQLITE_ENABLE_SERIES=1 -DSQLITE_ENABLE_UUID=1 -DSQLITE_ENABLE_REGEXP=1 -DSQLITE_TEMP_STORE=2 -DSQLITE_USE_URI=1 -DSQLITE_USER_AUTHENTICATION=1 $(X86_FLAGS) $(ARM_FLAGS)
 
+if HOST_WINDOWS
+AM_LDFLAGS =
+else
 AM_LDFLAGS = -pthread -ldl -lm
+endif
 
 if HOST_OSX
 AM_LDFLAGS += -framework Security