strfmon: Fix alignment when enclosed by parentheses

strfmon: Fix alignment when enclosed by parentheses

Take into consideration the possibility of quantities enclosed by
parentheses when aligning.

Matches the examples from The Open Group's:

Format  Before          After
%(#5n   [$   123.45]    [ $   123.45 ]  Use an alternative pos/neg style
        [($   123.45)]  [($   123.45)]
        [$ 3,456.78]    [ $ 3,456.78 ]

%!(#5n  [   123.45]     [    123.45 ]   Disable the currency symbol
        [(   123.45)]   [(   123.45)]
        [ 3,456.78]     [  3,456.78 ]

https://pubs.opengroup.org/onlinepubs/9699919799/functions/strfmon.html

SD5-XSH-ERN-29 is applied, updating the examples for %(#5n and %!(#5n.

Obtained from:	Darwin
Reviewed by:	kib
PR:	267282
Github PR:	#619
MFC after:	1 week