#2105 sprintf multi param format strings

[Moritz Buhl]

Hi,
I use the following sprintf function:

sprintf("%*d", width, num);

It takes two arguments. I think it is not supported by f_sprintf as it only passes one argument to
the system's sprintf.
Instead of fixing this, I suggest adding * to the illegal_spec array in sprintf_specifier.

[Ethan Merritt]

Good idea.
Applied