Fix SC2219 warnings

Author: nyalldawson

rpm/buildrpms.sh

@@ -87,7 +87,7 @@ then
   source version.cfg
   if [ "$build_only" -ne "1" ]
   then
-    let relver+=1
+    (( relver+=1 ))
     echo "relver=$relver" > version.cfg
   fi
   timestamp=0

tests/code_layout/test_shellcheck.sh

@@ -5,7 +5,7 @@
 DIR=$(git rev-parse --show-toplevel)
 
 pushd ${DIR} > /dev/null || exit
-result=$(shellcheck -e SC2016,SC2015,SC2086,SC2002,SC1117,SC2154,SC2076,SC2046,SC1090,SC2038,SC2031,SC2030,SC2162,SC2196,SC2034,SC2044,SC2119,SC1001,SC2188,SC2119,SC2188,SC2120,SC2103,SC2059,SC2006,SC2221,SC2222,SC2120,SC2128,SC2005,SC2004,SC2013,SC2027,SC2090,SC2089,SC2124,SC2068,SC2035,SC2001,SC2010,SC1072,SC1073,SC1009,SC2166,SC2062,SC2045,SC2028,SC1091,SC2181,SC1083,SC2116,SC2219 $(find . -name '*.sh'))
+result=$(shellcheck -e SC2016,SC2015,SC2086,SC2002,SC1117,SC2154,SC2076,SC2046,SC1090,SC2038,SC2031,SC2030,SC2162,SC2196,SC2034,SC2044,SC2119,SC1001,SC2188,SC2119,SC2188,SC2120,SC2103,SC2059,SC2006,SC2221,SC2222,SC2120,SC2128,SC2005,SC2004,SC2013,SC2027,SC2090,SC2089,SC2124,SC2068,SC2035,SC2001,SC2010,SC1072,SC1073,SC1009,SC2166,SC2062,SC2045,SC2028,SC1091,SC2181,SC1083,SC2116 $(find . -name '*.sh'))
 popd > /dev/null || exit
 
 if [[ $result ]]; then