ipsec: multi-arch, next-node-index cleanup

1. specify ipsec_xxx_node.c in MULTIARCH_SOURCES
2. cleanup foreach_ipsec_output_next & foreach_ipsec_input_next,
   as next-nodes are actually added by ipsec_register_xx_backend dynamically
   thus, ipsec4-input-feature will point to ah4/esp4-encrypt, instead of
   pointing to ah6/esp6-encrypt
3. remove an unused count and add counter IPSEC_INPUT_ERROR_RX_MATCH_PKTS
   in ipsec-input

Change-Id: Ifcf167812d2cc18187c2cea84b657a52b67e17d4
Signed-off-by: Kingwel Xie <kingwel.xie@ericsson.com>
diff --git a/src/vnet/ipsec/ipsec_io.h b/src/vnet/ipsec/ipsec_io.h
index aa6fa8d..c180a78 100644
--- a/src/vnet/ipsec/ipsec_io.h
+++ b/src/vnet/ipsec/ipsec_io.h
@@ -18,11 +18,7 @@
 #define IPSEC_FLAG_IPSEC_GRE_TUNNEL (1 << 0)
 
 #define foreach_ipsec_output_next  \
-  _ (DROP, "error-drop")           \
-  _ (ESP4_ENCRYPT, "esp4-encrypt") \
-  _ (AH4_ENCRYPT, "ah4-encrypt")   \
-  _ (ESP6_ENCRYPT, "esp6-encrypt") \
-  _ (AH6_ENCRYPT, "ah6-encrypt")
+  _ (DROP, "error-drop")
 
 #define _(v, s) IPSEC_OUTPUT_NEXT_##v,
 typedef enum
@@ -33,11 +29,7 @@
 } ipsec_output_next_t;
 
 #define foreach_ipsec_input_next   \
-  _ (DROP, "error-drop")           \
-  _ (ESP4_DECRYPT, "esp4-decrypt") \
-  _ (AH4_DECRYPT, "ah4-decrypt")   \
-  _ (ESP6_DECRYPT, "esp6-decrypt") \
-  _ (AH6_DECRYPT, "ah6-decrypt")
+  _ (DROP, "error-drop")
 
 #define _(v, s) IPSEC_INPUT_NEXT_##v,
 typedef enum