[PATCH] selftests/zram: fix kernel_gte() for POSIX sh

Commit fc4eb486a59d ("selftests/zram: Skip max_comp_streams
interface on newer kernel") added kernel_gte() to zram_lib.sh.
The function uses the bash-specific [[ ... ]] conditional, but
zram selftests source this file while running under /bin/sh.

On systems where /bin/sh is dash, such as Debian, the following
test fails:

  dash -c '
  kernel_major=6; kernel_minor=1; major=6; minor=0
  if [ $kernel_major -gt $major ]; then
      echo ok
  elif [[ $kernel_major -eq $major && $kernel_minor -ge $minor ]]; then
      echo ok
  fi'

with:

  dash: 5: [[: not found

Use separate POSIX test expressions joined by && instead.

Fixes: fc4eb486a59d ("selftests/zram: Skip max_comp_streams interface on newer kernel")
Signed-off-by: Cheng-Han Wu <[email protected]>
---
 tools/testing/selftests/zram/zram_lib.sh | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/tools/testing/selftests/zram/zram_lib.sh b/tools/testing/selftests/zram/zram_lib.sh
index 21ec1966de76..0d44d83888f9 100755
--- a/tools/testing/selftests/zram/zram_lib.sh
+++ b/tools/testing/selftests/zram/zram_lib.sh
@@ -37,7 +37,7 @@ kernel_gte()
 
 	if [ $kernel_major -gt $major ]; then
 		return 0
-	elif [[ $kernel_major -eq $major && $kernel_minor -ge $minor ]]; then
+	elif [ $kernel_major -eq $major ] && [ $kernel_minor -ge $minor ]; then
 		return 0
 	fi
 
-- 
2.52.0