meta-openpower: phosphor-logging: set version wildcard

Set the wildcard for version for phosphor-logging.bbappend

Change-Id: I3a64b775a1fbe9b2ba96c663fa07fdf6ae42b038
Signed-off-by: Patrick Venture <venture@google.com>
diff --git a/recipes-phosphor/logging/phosphor-logging_%.bbappend b/recipes-phosphor/logging/phosphor-logging_%.bbappend
new file mode 120000
index 0000000..42d87b7
--- /dev/null
+++ b/recipes-phosphor/logging/phosphor-logging_%.bbappend
@@ -0,0 +1 @@
+phosphor-logging.bbappend
\ No newline at end of file