testmgr: support newer kernels

Since the commit 0eb76ba29d16 ("crypto: remove cipher routines from
public crypto API") cipher routines (used by the test manager) were
pushed into separate header file (and separate namespace). Add
corresponding changes.

Signed-off-by: Dmitry Baryshkov <dbaryshkov@gmail.com>

testmgr.c

@@ -29,10 +29,10 @@
 #include <linux/slab.h>
 #include <linux/string.h>
 #include <linux/version.h>
-#if 0
-#include <crypto/aead.h>
-#include <crypto/akcipher.h>
-#include <crypto/kpp.h>
+
+#if LINUX_VERSION_CODE >= KERNEL_VERSION(5, 12, 0)
+#include <crypto/internal/cipher.h>
+MODULE_IMPORT_NS(CRYPTO_INTERNAL);
 #endif
 
 #if LINUX_VERSION_CODE < KERNEL_VERSION(5, 1, 0)