Allow 64-bit constants when yylval.lval is 64 bits.
 [jmk] --rw-rw-r-- M 137273 glenda sys 9186 Sep 21 08:56 sys/src/cmd/cc/lexbody
	/n/sourcesdump/2005/0921/plan9/sys/src/cmd/cc/lexbody:342,350 - 
	/n/sourcesdump/2005/0922/plan9/sys/src/cmd/cc/lexbody:342,355
	  		if(c == 'e' || c == 'E')
	  			goto casee;
	  		*cp = 0;
	- 		yylval.lval = atol(symb);
	+ 		if(sizeof(yylval.lval) == sizeof(vlong))
	+ 			yylval.lval = strtoll(symb, nil, 10);
	+ 		else
	+ 			yylval.lval = strtol(symb, nil, 10);
	  
	  	ncu:
	+ 		while(c == 'U' || c == 'u' || c == 'l' || c == 'L')
	+ 			c = GETC();
	  		peekc = c;
	  		return LCONST;
	  
 [jmk] --rwxrwxr-x M 137273 rsc sys 115969 Sep 21 23:42 386/bin/8a
	/sys/src/cmd/8a/a.y:yylex1
	/sys/src/cmd/8a/a.y:yytokname
	/sys/src/cmd/cc/lexbody:yylex
	/sys/src/libc/fmt/fmt.c:_fmtinstall
	/sys/src/libc/fmt/sprint.c:sprint
	/sys/src/libc/port/pool.c:blocksetdsize
	/sys/src/libc/port/pool.c:trim
	/sys/src/libc/port/rune.c:chartorune
	/sys/src/libc/port/strtol.c:strtol