Interface: Rename PSA headers

Renames PSA headers from psa_<api>.h to psa/<api>.h.

Change-Id: I3fc552c39f9a7e6d54e7a7a2f82f076bd03d30a7
Signed-off-by: Jamie Fox <jamie.fox@arm.com>
diff --git a/secure_fw/services/crypto/tfm_crypto_api.h b/secure_fw/services/crypto/tfm_crypto_api.h
index d74b251..da23f6f 100644
--- a/secure_fw/services/crypto/tfm_crypto_api.h
+++ b/secure_fw/services/crypto/tfm_crypto_api.h
@@ -15,9 +15,9 @@
 #include <stdint.h>
 #include "tfm_api.h"
 #include "tfm_crypto_defs.h"
-#include "psa_crypto.h"
+#include "psa/crypto.h"
 #ifdef TFM_PSA_API
-#include "psa_service.h"
+#include "psa/service.h"
 
 /**
  * \brief This define is a function pointer type to the Uniform Signature API