setup: update runcmd() to also return the exit status
Update the runcmd() helper function so it also returns the process exit status.
This allows callers to more definitively determine if a command failed, rather
than testing only for the presence of data on stderr.
I don't expect this to have any behavioral changes for now: the commands
invoked by setup generally should print data on stderr if and only if they
failed.
# See http://EditorConfig.org for the specification
root = true
[*.py]
indent_size = 4
indent_style = space
trim_trailing_whitespace = true
[*.{c,h}]
indent_size = 8
indent_style = tab
trim_trailing_whitespace = true