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

libtcc.c

@@ -1572,7 +1572,6 @@ static const FlagDef options_f[] = {
     { offsetof(TCCState, nocommon), FD_INVERT, "common" },
     { offsetof(TCCState, leading_underscore), 0, "leading-underscore" },
     { offsetof(TCCState, ms_extensions), 0, "ms-extensions" },
-    { offsetof(TCCState, old_struct_init_code), 0, "old-struct-init-code" },
     { offsetof(TCCState, dollars_in_identifiers), 0, "dollars-in-identifiers" },
     { 0, 0, NULL }
 };
@@ -1984,21 +1983,3 @@ PUB_FUNC void tcc_print_stats(TCCState *s, unsigned total_time)
     fprintf(stderr, "* %d bytes memory used\n", mem_max_size);
 #endif
 }
-
-PUB_FUNC void tcc_set_environment(TCCState *s)
-{
-    char * path;
-
-    path = getenv("C_INCLUDE_PATH");
-    if(path != NULL) {
-        tcc_add_include_path(s, path);
-    }
-    path = getenv("CPATH");
-    if(path != NULL) {
-        tcc_add_include_path(s, path);
-    }
-    path = getenv("LIBRARY_PATH");
-    if(path != NULL) {
-        tcc_add_library_path(s, path);
-    }
-}