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/Makefile

@@ -24,11 +24,9 @@ TARGET	= $(CPU)
 ifeq ($(TARGET), 64)
 TFLAGS	= -m$(TARGET) -DTCC_TARGET_X86_64
 TARCH	= x86_64
-CARCH	= x86-64
 else
 TFLAGS	= -m$(TARGET) -DTCC_TARGET_I386
 TARCH	= i386
-CARCH	= i386
 endif
 
 all: pre bootstrap libs rebuild
@@ -36,7 +34,7 @@ all: pre bootstrap libs rebuild
 	@ls -ls *.exe
 
 pre:
-	@echo ARCH=$(CARCH) 1> ../config.mak
+	@echo ARCH=$(TARCH) 1> ../config.mak
 	@echo TARGETOS=Windows  1>> ../config.mak
 	@echo CONFIG_WIN32=yes 1>> ../config.mak
 	@echo TOPSRC=$$\(TOP\) 1>> ../config.mak