build: Always enable -Wmisleading-indentation

Try and ensure that people don’t push code with misleading indentation
in future. This should give fairly few false positives.

Signed-off-by: Philip Withnall <withnall@endlessm.com>
6 jobs for 796385-indentation in 20 minutes and 16 seconds (queued for 4 seconds)
Status Job ID Name Coverage
  Build
passed #39338
fedora-meson-android_ndk_r16_api21_arm64

00:13:56

passed #39339
fedora-meson-mingw64

00:04:57

passed #39337
fedora-meson-x86_64

00:03:57

passed #39340
win32
msys2-mingw32

00:08:16

passed #39341
win32
vs2017-x64

00:06:00

 
  Coverage
passed #39342
coverage

00:06:01

76.8%