Add memfd related missing syscalls to allowed list

Bug: 113362644
Change-Id: I7ae3305ad12600a38faebf0b66cb5b954862df5e
Signed-off-by: Joel Fernandes <joelaf@google.com>
diff --git a/services/mediacodec/seccomp_policy/mediacodec-arm.policy b/services/mediacodec/seccomp_policy/mediacodec-arm.policy
index 0aa5acc..9bdd4c8 100644
--- a/services/mediacodec/seccomp_policy/mediacodec-arm.policy
+++ b/services/mediacodec/seccomp_policy/mediacodec-arm.policy
@@ -14,6 +14,7 @@
 mmap2: 1
 getrandom: 1
 memfd_create: 1
+ftruncate: 1
 ftruncate64: 1
 
 # mremap: Ensure |flags| are (MREMAP_MAYMOVE | MREMAP_FIXED) TODO: Once minijail