Support else-if predicate syntax

Backwards-compatible frontend only change (bumping cerberus-lib, adding
and updating tests).

Author: dc-mak

Makefile

@@ -29,7 +29,6 @@ full-build:
 cn:
 	@echo "[DUNE] $@"
 	$(Q)dune build -p cn
-	@echo -e "\nDONE"
 
 .PHONY: clean
 clean:

cn.opam

@@ -23,7 +23,7 @@ depends: [
   "zarith" {>= "1.13"}
 ]
 pin-depends: [
-  ["cerberus-lib.dev" "git+https://github.com/rems-project/cerberus.git#2d84326"]
+  ["cerberus-lib.dev" "git+https://github.com/rems-project/cerberus.git#62f0fcf"]
 ]
 build: [
   ["dune" "subst"] {pinned}

tests/cn/list_literal_type.error.c.verify

@@ -1,5 +1,5 @@
 return code: 2
 tests/cn/list_literal_type.error.c:3:15: error: unexpected token after 'list' and before '<'
-Please add error message for state 1842 to parsers/c/c_parser_error.messages
+Please add error message for state 1844 to parsers/c/c_parser_error.messages
 function (list<integer>) nonempty_list() {
               ^ 

tests/cn/predicate_else_if.c

@@ -0,0 +1,20 @@
+/*@
+predicate i32 IfChain(pointer p, i32 i) {
+    if (i <= 0i32) {
+      return 0i32;
+    } else if (i == 1i32) {
+      take X = Owned<int>(p);
+      return 0i32;
+    } else {
+      take X = Owned<int>(p);
+      take X2 = Owned(array_shift<int>(p,1u64));
+      return 0i32;
+   }
+}
+@*/    
+
+int main()
+{
+
+    return 0;
+}

tests/cn/predicate_else_if.c.verify

@@ -0,0 +1,5 @@
+return code: 0
+tests/cn/predicate_else_if.c:6:16: warning: deprecated keyword 'Owned', use 'RW' instead
+      take X = Owned<int>(p);
+               ^~~~~ 
+[1/1]: main -- pass