Remove some dead code

From the notes.ghc.drop list found using weeder in #17713
24 jobs for master in 407 minutes and 19 seconds (queued for 5 seconds)
Status Job ID Name Coverage
  Lint
passed #282021
lint
lint-linters

00:00:15

passed #282024
lint
lint-submods-branch

00:00:16

passed #282022
lint
lint-testsuite

00:00:17

passed #282023
lint
typecheck-testsuite

00:00:14

 
  Quick Build
passed #282025
x86_64-linux
hadrian-ghc-in-ghci

00:19:52

 
  Build
passed #282026
x86_64-linux
validate-x86_64-linux-deb9-hadrian

01:36:30

 
  Full Build
failed #282029
aarch64-linux allowed to fail
validate-aarch64-linux-deb9

03:02:27

passed #282030
armv7-linux
validate-armv7-linux-deb9

03:30:14

passed #282031
x86_64-linux
validate-i386-linux-deb9

00:55:59

failed #282038
new-x86_64-windows test allowed to fail
validate-i386-windows

00:00:52

passed #282028
x86_64-darwin
validate-x86_64-darwin

01:09:47

passed #282032
x86_64-linux
validate-x86_64-linux-deb9-debug

02:19:45

passed #282034
x86_64-linux
validate-x86_64-linux-deb9-dwarf

01:38:32

passed #282033
x86_64-linux
validate-x86_64-linux-deb9-integer-simple

01:02:04

passed #282027
x86_64-linux
validate-x86_64-linux-deb9-unreg-hadrian

04:31:21

passed #282035
x86_64-linux
validate-x86_64-linux-fedora27

01:49:38

failed #282037
new-x86_64-windows test allowed to fail
validate-x86_64-windows

03:07:59

failed #282036
new-x86_64-windows test allowed to fail
validate-x86_64-windows-hadrian

00:59:13

 
  Cleanup
passed #282039
x86_64-darwin
cleanup-darwin

00:00:23

 
  Packaging
passed #282040
x86_64-linux
doc-tarball

00:02:00

 
  Testing
manual #282041
x86_64-linux allowed to fail manual
hackage
passed #282042
x86_64-linux
perf-nofib

00:16:02

 
  Deploy
passed #282043
x86_64-linux
pages

00:00:31

failed pages:deploy

00:00:00

 
Name Stage Failure
failed
validate-aarch64-linux-deb9 Full Build
Uploading artifacts...
ghc-aarch64-linux-deb9.tar.xz: found 1 matching files
junit.xml: found 1 matching files

performance-metrics.tsv: found 1 matching files

Uploading artifacts to coordinator... ok
id=282029 responseStatus=201 Created token=eMYQcwT_
Uploading artifacts...
junit.xml: found 1 matching files

Uploading artifacts to coordinator... ok
id=282029 responseStatus=201 Created token=eMYQcwT_
ERROR: Job failed: exit code 1
failed
validate-x86_64-windows Full Build
GO version:   go1.13.4
Built: 2019-12-22T11:55:34+0000
OS/Arch: windows/amd64
Uploading artifacts...
Runtime platform
arch=amd64 os=windows pid=5500 revision=ac8e767a version=12.6.0
junit.xml: found 1 matching files

WARNING: Failed to load system CertPool: crypto/x509: system root pool is not available on Windows
Uploading artifacts to coordinator... ok
id=282037 responseStatus=201 Created token=3opiVxWW
ERROR: Job failed: exit status 1
failed
validate-x86_64-windows-hadrian Full Build
Git branch:   12-6-stable
GO version: go1.13.4
Built: 2019-12-22T11:55:34+0000
OS/Arch: windows/amd64
Uploading artifacts...
Runtime platform
arch=amd64 os=windows pid=2896 revision=ac8e767a version=12.6.0
WARNING: junit.xml: no matching files
ERROR: No files to upload
ERROR: Job failed: exit status 1
failed
validate-i386-windows Full Build
Git branch:   12-6-stable
GO version: go1.13.4
Built: 2019-12-22T11:55:34+0000
OS/Arch: windows/amd64
Uploading artifacts...
Runtime platform
arch=amd64 os=windows pid=1532 revision=ac8e767a version=12.6.0
WARNING: junit.xml: no matching files
ERROR: No files to upload
ERROR: Job failed: exit status 1