Fix SC2181 ("[ $?") outside tests/

Reviewed-by: John Kennedy <john.kennedy@delphix.com>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Ahelenia Ziemiańska <nabijaczleweli@nabijaczleweli.xyz>
Closes #12042

scripts/commitcheck.sh

@@ -87,9 +87,7 @@ coverity_fix_commit()
     IFS='
 '
     for line in $(git log -n 1 --pretty=%b "$REF" | grep -E '^CID'); do
-        echo "$line" | grep -E '^CID [[:digit:]]+: ([[:graph:]]+|[[:space:]])+ \(([[:upper:]]|\_)+\)' > /dev/null
-        # shellcheck disable=SC2181
-        if [ $? -ne 0 ]; then
+        if ! echo "$line" | grep -qE '^CID [[:digit:]]+: ([[:graph:]]+|[[:space:]])+ \(([[:upper:]]|\_)+\)'; then
             echo "error: commit message has an improperly formatted CID defect line"
             error=1
         fi

scripts/zfs.sh

@@ -120,9 +120,7 @@ load_module_linux() {
 		echo "Loading: $FILE ($VERSION)"
 	fi
 
-	$LDMOD "$KMOD" >/dev/null 2>&1
-	# shellcheck disable=SC2181
-	if [ $? -ne 0 ]; then
+	if ! $LDMOD "$KMOD" >/dev/null 2>&1; then
 		echo "Failed to load $KMOD"
 		return 1
 	fi

scripts/zimport.sh

@@ -491,10 +491,8 @@ for TAG in $POOL_TAGS; do
 		POOL_NAME=$($ZPOOL_CMD import -d "$POOL_DIR_COPY" | \
 		    awk '/pool:/ { print $2; exit 0 }')
 
-		$ZPOOL_CMD import -N -d "$POOL_DIR_COPY" \
-		   "$POOL_NAME" &>/dev/null
-		# shellcheck disable=SC2181
-		if [ $? -ne 0 ]; then
+		if ! $ZPOOL_CMD import -N -d "$POOL_DIR_COPY"
+		    "$POOL_NAME" &>/dev/null; then
 			fail_nonewline
 			ERROR=1
 		else

scripts/zloop.sh

@@ -62,11 +62,8 @@ function usage
 function or_die
 {
 	# shellcheck disable=SC2068
-	$@
-	# shellcheck disable=SC2181
-	if [[ $? -ne 0 ]]; then
-		# shellcheck disable=SC2145
-		echo "Command failed: $@"
+	if ! $@; then
+		echo "Command failed: $*"
 		exit 1
 	fi
 }