[nrf fromtree] bootutil: Fix log module registration

Use BOOT_LOG_MODULE_REGISTER(mcuboot_psa_enc), instead
of BOOT_LOG_MODULE_DECLARE.

Signed-off-by: Dominik Ermel <dominik.ermel@nordicsemi.no>
(cherry picked from commit 8a07053)

Author: de-nordic

boot/bootutil/src/encrypted_psa.c

@@ -25,7 +25,7 @@
 #include "bootutil_priv.h"
 #include "bootutil/bootutil_log.h"
 
-BOOT_LOG_MODULE_DECLARE(mcuboot_psa_enc);
+BOOT_LOG_MODULE_REGISTER(mcuboot_psa_enc);
 
 #if defined(MCUBOOT_HMAC_SHA512)
 #define PSA_HMAC_HKDF_SHA PSA_ALG_SHA_512