meta-google: inplace-gbmc-update: Fix shellcheck issues

Change-Id: Ie8f8623b00f5eb1d830fc93d79b43406078db2f6
Signed-off-by: William A. Kennington III <wak@google.com>
diff --git a/meta-google/recipes-phosphor/flash/inplace-gbmc-update/inplace-gbmc-verify.sh b/meta-google/recipes-phosphor/flash/inplace-gbmc-update/inplace-gbmc-verify.sh
index e7727cd..8668ba9 100644
--- a/meta-google/recipes-phosphor/flash/inplace-gbmc-update/inplace-gbmc-verify.sh
+++ b/meta-google/recipes-phosphor/flash/inplace-gbmc-update/inplace-gbmc-verify.sh
@@ -22,7 +22,6 @@
 # 1. Verify the image
 # 2. Rename the image
 
-KEYRING=/etc/googlekeys/gbmc/gbmc.gpg
 SIGNATURE_FILE=/tmp/bmc.sig
 STATUS_FILE=/tmp/bmc.verify