[e-acsl] new option -e-acsl-gmp-only: used in tests to check the GMP translation

...-acsl/tests/e-acsl-runtime/oracle/gen_function_contract.c

...acsl/tests/e-acsl-runtime/oracle/gen_function_contract2.c

...e-acsl/tests/e-acsl-runtime/oracle/gen_integer_constant.c

...-acsl/tests/e-acsl-runtime/oracle/gen_integer_constant2.c

...lugins/e-acsl/tests/e-acsl-runtime/oracle/gen_invariant.c

...ugins/e-acsl/tests/e-acsl-runtime/oracle/gen_invariant2.c

...ins/e-acsl/tests/e-acsl-runtime/oracle/gen_labeled_stmt.c

...ns/e-acsl/tests/e-acsl-runtime/oracle/gen_labeled_stmt2.c

src/plugins/e-acsl/tests/e-acsl-runtime/oracle/gen_lazy.c

src/plugins/e-acsl/tests/e-acsl-runtime/oracle/gen_lazy2.c

...ns/e-acsl/tests/e-acsl-runtime/oracle/gen_linear_search.c

...s/e-acsl/tests/e-acsl-runtime/oracle/gen_linear_search2.c

...-acsl/tests/e-acsl-runtime/oracle/gen_nested_code_annot.c

...acsl/tests/e-acsl-runtime/oracle/gen_nested_code_annot2.c

src/plugins/e-acsl/tests/e-acsl-runtime/oracle/gen_not.c

src/plugins/e-acsl/tests/e-acsl-runtime/oracle/gen_not2.c

src/plugins/e-acsl/tests/e-acsl-runtime/oracle/gen_null.c

src/plugins/e-acsl/tests/e-acsl-runtime/oracle/gen_null2.c

.../e-acsl/tests/e-acsl-runtime/oracle/gen_other_constants.c

...e-acsl/tests/e-acsl-runtime/oracle/gen_other_constants2.c