make-memstick.sh: use 'set -e' to abort if any step fails

Also remove the now-redundant error handling that was only for makefs.

This change applies arm64's r308171 to the other make-memstick.sh
versions.

Reviewed by:	gjb
MFC after:	1 week
Sponsored by:	The FreeBSD Foundation
Differential Revision:	https://reviews.freebsd.org/D12195

release/amd64/make-memstick.sh

@@ -10,6 +10,8 @@
 # $FreeBSD$
 #
 
+set -e
+
 PATH=/bin:/usr/bin:/sbin:/usr/sbin
 export PATH
 
@@ -31,10 +33,6 @@ fi
 echo '/dev/ufs/FreeBSD_Install / ufs ro,noatime 1 1' > ${1}/etc/fstab
 echo 'root_rw_mount="NO"' > ${1}/etc/rc.conf.local
 makefs -B little -o label=FreeBSD_Install ${2}.part ${1}
-if [ $? -ne 0 ]; then
-	echo "makefs failed"
-	exit 1
-fi
 rm ${1}/etc/fstab
 rm ${1}/etc/rc.conf.local
 

release/i386/make-memstick.sh

@@ -10,6 +10,8 @@
 # $FreeBSD$
 #
 
+set -e
+
 PATH=/bin:/usr/bin:/sbin:/usr/sbin
 export PATH
 
@@ -31,10 +33,6 @@ fi
 echo '/dev/ufs/FreeBSD_Install / ufs ro,noatime 1 1' > ${1}/etc/fstab
 echo 'root_rw_mount="NO"' > ${1}/etc/rc.conf.local
 makefs -B little -o label=FreeBSD_Install ${2}.part ${1}
-if [ $? -ne 0 ]; then
-	echo "makefs failed"
-	exit 1
-fi
 rm ${1}/etc/fstab
 rm ${1}/etc/rc.conf.local
 

release/powerpc/make-memstick.sh

@@ -10,6 +10,8 @@
 # $FreeBSD$
 #
 
+set -e
+
 PATH=/bin:/usr/bin:/sbin:/usr/sbin
 export PATH
 
@@ -36,10 +38,6 @@ echo '/dev/da0s3 / ufs ro,noatime 1 1' > ${1}/etc/fstab
 echo 'root_rw_mount="NO"' > ${1}/etc/rc.conf.local
 rm -f ${tempfile}
 makefs -B big ${tempfile} ${1}
-if [ $? -ne 0 ]; then
-  echo "makefs failed"
-  exit 1
-fi
 rm ${1}/etc/fstab
 rm ${1}/etc/rc.conf.local