[ghost] Renames some files

tests/syntax/oracle/ghost-else-bad.1.err.oracle

-Warning: tests/syntax/ghost-else-bad.c:32: Invalid ghost else ignored

tests/syntax/oracle/ghost-else.res.oracle → tests/syntax/oracle/ghost_else.res.oracle

-[kernel] Parsing tests/syntax/ghost-else.i (no preprocessing)
+[kernel] Parsing tests/syntax/ghost_else.i (no preprocessing)
 /* Generated by Frama-C */
 /*  run.config
    OPT: -no-autoload-plugins -keep-comments -print

tests/syntax/oracle/ghost-else-bad.0.res.oracle → tests/syntax/oracle/ghost_else_bad.0.res.oracle

-[kernel] Parsing tests/syntax/ghost-else-bad.c (with preprocessing)
-[kernel] tests/syntax/ghost-else-bad.c:20: User Error: Cannot resolve variable z
-[kernel] User Error: stopping on file "tests/syntax/ghost-else-bad.c" that has errors. Add
+[kernel] Parsing tests/syntax/ghost_else_bad.c (with preprocessing)
+[kernel] tests/syntax/ghost_else_bad.c:20: User Error: Cannot resolve variable z
+[kernel] User Error: stopping on file "tests/syntax/ghost_else_bad.c" that has errors. Add
   '-kernel-msg-key pp' for preprocessing command.
 [kernel] Frama-C aborted: invalid user input.

tests/syntax/oracle/ghost_else_bad.1.err.oracle

+Warning: tests/syntax/ghost_else_bad.c:32: Invalid ghost else ignored

tests/syntax/oracle/ghost-else-bad.1.res.oracle → tests/syntax/oracle/ghost_else_bad.1.res.oracle

-[kernel] Parsing tests/syntax/ghost-else-bad.c (with preprocessing)
+[kernel] Parsing tests/syntax/ghost_else_bad.c (with preprocessing)
 /* Generated by Frama-C */
 void if_ghost_else_block_bad(int x, int y)
 {

tests/syntax/oracle/ghost-else-bad.2.res.oracle → tests/syntax/oracle/ghost_else_bad.2.res.oracle

-[kernel] Parsing tests/syntax/ghost-else-bad.c (with preprocessing)
-[kernel] tests/syntax/ghost-else-bad.c:47: 
+[kernel] Parsing tests/syntax/ghost_else_bad.c (with preprocessing)
+[kernel] tests/syntax/ghost_else_bad.c:47: 
   syntax error:
   Location: between lines 47 and 49, before or at token: else
   45      if(x){

tests/syntax/oracle/ghost-else-bad-oneline.res.oracle → tests/syntax/oracle/ghost_else_bad_oneline.res.oracle

-[kernel] Parsing tests/syntax/ghost-else-bad-oneline.i (no preprocessing)
-[kernel] tests/syntax/ghost-else-bad-oneline.i:6: 
+[kernel] Parsing tests/syntax/ghost_else_bad_oneline.i (no preprocessing)
+[kernel] tests/syntax/ghost_else_bad_oneline.i:6: 
   syntax error:
   Location: between lines 6 and 8, before or at token: