rootfs.py: close kernel_abi_ver_file

* fixes:
  oe-core/meta/lib/oe/rootfs.py:331: ResourceWarning: unclosed file <_io.TextIOWrapper name='pkgdata/mach/kernel-depmod/kernel-abiversion' mode='r' encoding='UTF-8'>
  kernel_ver = open(kernel_abi_ver_file).read().strip(' \n')

(From OE-Core rev: b761150790231792b42a8eb534013f1e17b4efb3)

Signed-off-by: Martin Jansa <Martin.Jansa@gmail.com>
Signed-off-by: Luca Ceresoli <luca.ceresoli@bootlin.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>
(cherry picked from commit f9dd8ee063c1132265248457fcd628e1e93727be)
Signed-off-by: Steve Sakoman <steve@sakoman.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

1 files changed, 3 insertions, 1 deletions

diff --git a/meta/lib/oe/rootfs.py b/meta/lib/oe/rootfs.py
index 9e9f7f1f08..5391c25af9 100644
--- a/meta/lib/oe/rootfs.py
+++ b/meta/lib/oe/rootfs.py
@@ -321,7 +321,9 @@ class Rootfs(object, metaclass=ABCMeta):
         if not os.path.exists(kernel_abi_ver_file):
             bb.fatal("No kernel-abiversion file found (%s), cannot run depmod, aborting" % kernel_abi_ver_file)
 
-        kernel_ver = open(kernel_abi_ver_file).read().strip(' \n')
+        with open(kernel_abi_ver_file) as f:
+            kernel_ver = f.read().strip(' \n')
+
         versioned_modules_dir = os.path.join(self.image_rootfs, modules_dir, kernel_ver)
 
         bb.utils.mkdirhier(versioned_modules_dir)