font/sfnt: fix parsing PostScript fonts' 4-byte numbers
font/sfnt: fix parsing PostScript fonts' 4-byte numbers

Fixes golang/go#46836

Change-Id: Ie4ff2a9866d3f468d973e73857d6c44078c0695d
Reviewed-on: https://go-review.googlesource.com/c/image/+/329949
Trust: Nigel Tao <58ae08b3356928ff9c67562b4719487d54fe8348@golang.org>
Run-TryBot: Nigel Tao <58ae08b3356928ff9c67562b4719487d54fe8348@golang.org>
TryBot-Result: Go Bot <66cb808b70d30c07676d5e946fee83fd561249e5@golang.org>
Reviewed-by: Rob Pike <4dc7c9ec434ed06502767136789763ec11d2c4b7@golang.org>

golang/image