[dev.regabi] cmd/compile: unexport reflectdata.WriteType
[dev.regabi] cmd/compile: unexport reflectdata.WriteType

WriteType isn't safe for direct concurrent use, and users should
instead use TypeLinksym or another higher-level API provided by
reflectdata. After the previous CL, there are no remaining uses of
WriteType elsewhere in the compiler, so unexport it to keep it that
way.

For #43701.

[git-generate]
cd src/cmd/compile/internal/reflectdata
rf '
	mv WriteType writeType
'

Change-Id: I294a78be570a47feb38a1ad4eaae7723653d5991
Reviewed-on: https://go-review.googlesource.com/c/go/+/284077
Trust: Matthew Dempsky <e56ac2c500064424afac424d4b5e53bd0570a731@google.com>
Run-TryBot: Matthew Dempsky <e56ac2c500064424afac424d4b5e53bd0570a731@google.com>
TryBot-Result: Go Bot <66cb808b70d30c07676d5e946fee83fd561249e5@golang.org>
Reviewed-by: Cuong Manh Le <54b4457f1dff6823379654eb5867596497ba782f@gmail.com>

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