meta-ibm: Rename bb file collections

Typical upstream layers have a -layer suffix.  Rename collections from
foo to foo-layer to match this de-facto standard.  Some existing layers
that use this convention include:

openembedded-layer
networking-layer
perl-layer
virtualization-layer

(From meta-ibm rev: 32478afb0f68ba711b816d1dbaecf379c67cc928)

Change-Id: I5c22956cf289263d5cef1e3c1babb2d1f5a10a3d
Signed-off-by: Brad Bishop <bradleyb@fuzziesquirrel.com>
diff --git a/meta-ibm/meta-z/conf/layer.conf b/meta-ibm/meta-z/conf/layer.conf
index 790dc69..252db1d 100644
--- a/meta-ibm/meta-z/conf/layer.conf
+++ b/meta-ibm/meta-z/conf/layer.conf
@@ -1,5 +1,5 @@
 # We have a conf and classes directory, add to BBPATH
 BBPATH .= ":${LAYERDIR}"
 
-BBFILE_COLLECTIONS += "ibm-z"
-BBFILE_PATTERN_ibm-z = ""
+BBFILE_COLLECTIONS += "ibm-z-layer"
+BBFILE_PATTERN_ibm-z-layer = ""