[perl #126626] my with parens should allow SSA binding at least one of these ways

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# New Ticket Created by  Larry Wall 
# Please include the string:  [perl #126626]
# in the subject line of all future correspondence about this issue. 
# <URL: https://rt.perl.org/Ticket/Display.html?id=126626 >


> p6 'my ($a, \b) = 1, 2; say $a; say b;'
1
(Any)
> p6 'my ($a, \b) := 1, 2; say $a; say b;'
1
(Any)
> p6 'my ($a, \b) ::= 1, 2; say $a; say b;'
1
(Any)
> p6 'my ($a, \b) ::= \(1,2); say $a; say b;'
1
(Any)