DOC: spoa/python: Fixing typo in IP related error messages

This commit fixes typos in the ps_python_set_var_ip* byte manipulation error
messages

This patch must be backported as far as 2.0.
diff --git a/contrib/spoa_server/ps_python.c b/contrib/spoa_server/ps_python.c
index 81bb932..ec97f30 100644
--- a/contrib/spoa_server/ps_python.c
+++ b/contrib/spoa_server/ps_python.c
@@ -236,7 +236,7 @@
 	if (value == NULL)
 		return NULL;
 	if (PY_STRING_GET_SIZE(value) != sizeof(ip)) {
-		PyErr_Format(spoa_error, "UPv6 manipulation internal error");
+		PyErr_Format(spoa_error, "IPv4 manipulation internal error");
 		return NULL;
 	}
 	memcpy(&ip, PY_STRING_AS_STRING(value), PY_STRING_GET_SIZE(value));
@@ -273,7 +273,7 @@
 	if (value == NULL)
 		return NULL;
 	if (PY_STRING_GET_SIZE(value) != sizeof(ip)) {
-		PyErr_Format(spoa_error, "UPv6 manipulation internal error");
+		PyErr_Format(spoa_error, "IPv6 manipulation internal error");
 		return NULL;
 	}
 	memcpy(&ip, PY_STRING_AS_STRING(value), PY_STRING_GET_SIZE(value));