free cleanup almost the finale

Add OPENSSL_clear_free which merges cleanse and free.
(Names was picked to be similar to BN_clear_free, etc.)
Removed OPENSSL_freeFunc macro.
Fixed the small simple ones that are left:
        CRYPTO_free CRYPTO_free_locked OPENSSL_free_locked

Reviewed-by: Richard Levitte <levitte@openssl.org>
diff --git a/crypto/rsa/rsa_eay.c b/crypto/rsa/rsa_eay.c
index 73a8e07..49c157a 100644
--- a/crypto/rsa/rsa_eay.c
+++ b/crypto/rsa/rsa_eay.c
@@ -243,10 +243,7 @@
         BN_CTX_end(ctx);
         BN_CTX_free(ctx);
     }
-    if (buf != NULL) {
-        OPENSSL_cleanse(buf, num);
-        OPENSSL_free(buf);
-    }
+    OPENSSL_clear_free(buf, num);
     return (r);
 }
 
@@ -480,10 +477,7 @@
         BN_CTX_end(ctx);
         BN_CTX_free(ctx);
     }
-    if (buf != NULL) {
-        OPENSSL_cleanse(buf, num);
-        OPENSSL_free(buf);
-    }
+    OPENSSL_clear_free(buf, num);
     return (r);
 }
 
@@ -622,10 +616,7 @@
         BN_CTX_end(ctx);
         BN_CTX_free(ctx);
     }
-    if (buf != NULL) {
-        OPENSSL_cleanse(buf, num);
-        OPENSSL_free(buf);
-    }
+    OPENSSL_clear_free(buf, num);
     return (r);
 }
 
@@ -725,10 +716,7 @@
         BN_CTX_end(ctx);
         BN_CTX_free(ctx);
     }
-    if (buf != NULL) {
-        OPENSSL_cleanse(buf, num);
-        OPENSSL_free(buf);
-    }
+    OPENSSL_clear_free(buf, num);
     return (r);
 }