pk/pk_wrap: replace ECDSA_C with generic ECDSA capabilities' defines

Signed-off-by: Valerio Setti <valerio.setti@nordicsemi.no>
diff --git a/library/pk_wrap.h b/library/pk_wrap.h
index 67d0989..f15359d 100644
--- a/library/pk_wrap.h
+++ b/library/pk_wrap.h
@@ -125,7 +125,7 @@
 extern const mbedtls_pk_info_t mbedtls_eckeydh_info;
 #endif
 
-#if defined(MBEDTLS_ECDSA_C)
+#if defined(MBEDTLS_PK_CAN_ECDSA_SIGN) || defined(MBEDTLS_PK_CAN_ECDSA_VERIFY)
 extern const mbedtls_pk_info_t mbedtls_ecdsa_info;
 #endif