libmbedtls: Use single-line string literals.

Signed-off-by: Guido Vranken <guidovranken@gmail.com>
[Cherry-pick upstream commit 962e4ee4a6b3, add libmbedtls: prefix]
Signed-off-by: Jerome Forissier <jerome@forissier.org>
diff --git a/lib/libmbedtls/mbedtls/library/md4.c b/lib/libmbedtls/mbedtls/library/md4.c
index 0fc1f5e..48b4ccd 100644
--- a/lib/libmbedtls/mbedtls/library/md4.c
+++ b/lib/libmbedtls/mbedtls/library/md4.c
@@ -414,8 +414,7 @@
     { "message digest" },
     { "abcdefghijklmnopqrstuvwxyz" },
     { "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789" },
-    { ("12345678901234567890123456789012345678901234567890123456789012"
-      "345678901234567890") }
+    { "12345678901234567890123456789012345678901234567890123456789012345678901234567890" }
 };
 
 static const size_t md4_test_strlen[7] =