selftests: do not require bash for the generated test

[ Upstream commit a2b1e8a2 ]

Nothing in this minimal script seems to require bash. We often run these
tests on embedded devices where the only shell available is the busybox
ash. Use sh instead.
Signed-off-by: Rolf Eike Beer <eb@emlix.com>
Cc: stable@vger.kernel.org
Signed-off-by: Shuah Khan <shuahkh@osg.samsung.com>
Signed-off-by: Sasha Levin <alexander.levin@verizon.com>

tools/testing/selftests/Makefile

@@ -70,7 +70,7 @@ ifdef INSTALL_PATH
 	done;
 
 	@# Ask all targets to emit their test scripts
-	echo "#!/bin/bash" > $(ALL_SCRIPT)
+	echo "#!/bin/sh" > $(ALL_SCRIPT)
 	echo "cd \$$(dirname \$$0)" >> $(ALL_SCRIPT)
 	echo "ROOT=\$$PWD" >> $(ALL_SCRIPT)