tcc: re-enable correct option -r support

Forgot about it.  It allows to compile several
sources (and other .o's) to one single .o file;

    tcc -r -o all.o f1.c f2.c f3.S o4.o ...

Also:
- option -fold-struct-init-code removed, no effect anymore
- (tcc_)set_environment() moved to tcc.c
- win32/lib/(win)crt1 minor fix & add dependency
- debug line output for asm (tcc -c -g xxx.S) enabled
- configure/Makefiles: x86-64 -> x86_64 changes
- README: cleanup

win32/lib/user32.def

@@ -336,6 +336,10 @@ GetWindow
 GetWindowContextHelpId
 GetWindowDC
 GetWindowInfo
+GetWindowLongPtrA
+GetWindowLongPtrW
+SetWindowLongPtrA
+SetWindowLongPtrW
 GetWindowLongA
 GetWindowLongW
 GetWindowModuleFileNameA