spec: clarify behavior of map size hint for make built-in
spec: clarify behavior of map size hint for make built-in

The spec already states that the precise behavior of the map size
hint provided to the make built-in is implementation-dependent.

Exclude requiring specific run-time behavior for maps.
(The current Go compiler does not panic if the size hint is negative
at run-time.)

Fixes #53219.

Change-Id: I2f3618bf9ba4ed921e18dc4f2273eaa770805bd7
Reviewed-on: https://go-review.googlesource.com/c/go/+/411919
Reviewed-by: Keith Randall <8c99c3a9284e493be632950b84cd789d08ed3e9d@google.com>
Reviewed-by: Ian Lance Taylor <87e9c6d529889242b7e184afb632328636553ab4@google.com>
Reviewed-by: Keith Randall <8c99c3a9284e493be632950b84cd789d08ed3e9d@golang.org>

golang/go,golang/go,golang/go,nawawi/go,nawawi/go,nawawi/go,golang/go,golang/go,nawawi/go,golang/go,nawawi/go,golang/go,nawawi/go,golang/go,nawawi/go,nawawi/go