correct version of "Identifiers can start and/or contain"

A problem was in TOK_ASMDIR_text:
    -    sprintf(sname, ".%s", get_tok_str(tok1, NULL));
    +    sprintf(sname, "%s", get_tok_str(tok1, NULL));
    When tok1 is '.text', then sname is '..text'

tcc.h

@@ -974,7 +974,9 @@ struct TCCState {
 
 #define DEF_ASM(x) DEF(TOK_ASM_ ## x, #x)
 #define TOK_ASM_int TOK_INT
-#define TOK_ASM_weak TOK_WEAK1
+#define DEF_ASMDIR(x) DEF(TOK_ASMDIR_ ## x, "." #x)
+#define TOK_ASMDIR_FIRST TOK_ASMDIR_byte
+#define TOK_ASMDIR_LAST TOK_ASMDIR_section
 
 #if defined TCC_TARGET_I386 || defined TCC_TARGET_X86_64
 /* only used for i386 asm opcodes definitions */