package/linux-tools/S10hyperv: fix shellcheck warnings

When running "make check-package" on a system with shellcheck 0.9.0,
the command fails with output:

    make check-package
    package/linux-tools/S10hyperv:0: run 'shellcheck' and fix the warnings
    ...
    2 warnings generated

This commit fixes the warnings reported by the command:

    shellcheck package/linux-tools/S10hyperv

This commit also fixes the four-space indent by a single tab on the
changed lines. Since this fixes the indentation warnings of
check-package, the Indent exclusion in .checkpackageignore is also
removed.

Fixes:

    In package/linux-tools/S10hyperv line 27:
        return $ret
               ^--^ SC2086 (info): Double quote to prevent globbing and word splitting.

    In package/linux-tools/S10hyperv line 48:
        return $ret
               ^--^ SC2086 (info): Double quote to prevent globbing and word splitting.

Signed-off-by: Julien Olivain <ju.o@free.fr>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@bootlin.com>

.checkpackageignore

@@ -94,7 +94,7 @@ package/libftdi/0002-libftdi.pc-requires-libusb-fix-static-build.patch Sob
 package/libiio/S99iiod Shellcheck Variables
 package/libmad/0001-mips-h-constraint-removal.patch Sob
 package/lighttpd/S50lighttpd EmptyLastLine Indent Shellcheck Variables
-package/linux-tools/S10hyperv Indent Variables
+package/linux-tools/S10hyperv Variables
 package/linuxptp/S65ptp4l Indent Shellcheck
 package/linuxptp/S66phc2sys Indent Shellcheck
 package/lirc-tools/S25lircd Indent Variables

package/linux-tools/S10hyperv

@@ -24,7 +24,7 @@ start() {
 	for prog in ${PROGS}; do
 		start_one "${prog}" || ret=$?
 	done
-    return $ret
+	return "$ret"
 }
 
 stop_one() {
@@ -45,7 +45,7 @@ stop() {
 	for prog in ${PROGS}; do
 		stop_one "${prog}" || ret=$?
 	done
-    return $ret
+	return "$ret"
 }
 
 restart() {