route/tc: avoid integer overflow in rtnl_tc_calc_cell_log()

Coverity doesn't like this. Workaround.

    Error: CPPCHECK_WARNING (CWE-190): [#def97]
    libnl-3.8.0/lib/route/tc.c:681: error[integerOverflow]: Signed integer overflow for expression '1<<i'.
    #  679|
    #  680|   	for (i = 0; i < 32; i++)
    #  681|-> 		if ((1 << i) == cell_size)
    #  682|   			return i;
    #  683|
1 file changed