gluster: fix event message to display no. of bricks removed

Add no. of bricks and volume details to the commit remove
brick event message.

Change-Id: I8ab4cf126812d3cd9a42348e35b0a60fd29d59ca
Bug-Url: https://bugzilla.redhat.com/show_bug.cgi?id=1035124
Signed-off-by: Timothy Asir <tjeyasin@redhat.com>