Don't call Load/FreeLibrary from DllMain

Other thread related stuff has been altered as well.
The music player thread now persists after playback is stopped.
It is suspended until the next MCI_PLAY command, instead of a new
thread being made for each MCI_PLAY command.

This fixes a deadlock case when playback was stopped and played
several times in very short succession.

Makefile

@@ -6,7 +6,7 @@ wav-winmm.rc.o: wav-winmm.rc.in
 	sed 's/__REV__/$(REV)/g' wav-winmm.rc.in | sed 's/__FILE__/wav-winmm/g' | mingw32-windres -O coff -o wav-winmm.rc.o
 
 wav-winmm.dll: wav-winmm.c wav-winmm.rc.o wav-winmm.def player.c stubs.c
-	mingw32-gcc -std=gnu99 -Wl,--enable-stdcall-fixup -Ilibs/include -O2 -shared -s -o winmm.dll wav-winmm.c player.c stubs.c wav-winmm.def wav-winmm.rc.o -L. -lvorbisfile-3 -lwinmm -static-libgcc
+	mingw32-gcc -std=gnu99 -Wl,--enable-stdcall-fixup -Ilibs/include -O2 -shared -s -o wav-winmm.dll wav-winmm.c player.c stubs.c wav-winmm.def wav-winmm.rc.o -L. -lvorbisfile-3 -lwinmm -static-libgcc
 
 clean:
-	rm -f winmm.dll wav-winmm.rc.o
+	rm -f wav-winmm.dll wav-winmm.rc.o

player.h

@@ -1,7 +1,10 @@
+#ifndef PLAYER_H
+#define PLAYER_H
+
 void plr_stop();
 void plr_volume(int vol);
 int plr_pump();
 int plr_length(const char *path);
 int plr_play(const char *path);
 
-void setWinmmDll(HINSTANCE inPtr);
+#endif