[WP] fixes a typo in a test.

src/plugins/wp/tests/wp_acsl/issue_A228.c

-Bool A, B;
+_Bool A, B;
 
 /*@
   ensures GOAL: \result ≡ 255;

src/plugins/wp/tests/wp_acsl/oracle/issue_A228.res.oracle

 # frama-c -wp [...]
 [kernel] Parsing tests/wp_acsl/issue_A228.c (with preprocessing)
-[kernel] :0: 
-  syntax error:
-  Location: between <unknown> and 1:5, before or at token: A
-  
-  1     Bool A, B;
-  
-  2     
-  3     /*@
-[kernel] Frama-C aborted: invalid user input.
+[wp] Running WP plugin...
+[wp] Warning: Missing RTE guards
+------------------------------------------------------------
+  Function job
+------------------------------------------------------------
+
+Goal Post-condition 'GOAL' in 'job':
+Assume { Type: is_bool(A) /\ is_bool(B). }
+Prove: land(-64, lor(to_uint32(lsl(A, 6)), to_uint32(lsl(B, 7)))) = 192.
+
+------------------------------------------------------------