misc/cgo/test: test C.enum_*
Allocate a C enum object, and test if it can be assigned a value
successfully.
For #39537
Change-Id: I7b5482112486440b9d99f2ee4051328d87f45dca
GitHub-Last-Rev:
81890f40acc5589563ec1206fe119873fb46dc1b
GitHub-Pull-Request: golang/go#39977
Reviewed-on: https://go-review.googlesource.com/c/go/+/240697
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Trust: Emmanuel Odeke <emmanuel@orijtech.com>