This function doesn't follow our convention of naming functions.

To allow for fault injection of the virCommand dry run,
add the ability to register a callback. The callback will
be passed the argv, env and stdin buffer and is expected
to return the exit status and optionally fill stdout and
stderr buffers.
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

Commit a1cbe4b5 added a check for spaces around assignments and this
patch extends it to checks for spaces around '=='.  One exception is
virAssertCmpInt where comma after '==' is acceptable (since it is a
macro and '==' is its argument).
Signed-off-by: NMartin Kletzander <mkletzan@redhat.com>

So far it's just virCommandSetDryRun.

Adding tests for new virKMod{Config|Load|Unload}() API's.

A test for virKModIsBlacklisted() would require some setup which cannot
be assumed.