[SYCLomatic] EOF terminates token traversal to avoid infinite loop

[the-slow-one]

While looking for "volatile" token, terminate at EOF token. If we don't do this explicitly Lexer::getRawToken keeps returning EOF on every subsequent invocation.

Signed by: Deepak Raj H R

[zhimingwang36]

Please fix the clang-format

[AndyCHHuang]

the implementation looks good to me.

consider making the 4000+ lines dummy char into the same line.
but it's optional.

[the-slow-one]

Failed tests are unrelated to this PR

[2024-09-24T17:11:24.336Z] Failed Tests (5):
[2024-09-24T17:11:24.336Z]   Clang :: dpct/codepin/report/change_floating_point_default_tolerances/test.cpp
[2024-09-24T17:11:24.336Z]   Clang :: dpct/codepin/report/dismatch_format/test.cpp
[2024-09-24T17:11:24.336Z]   Clang :: dpct/codepin/report/floating_point_compare/test.cpp
[2024-09-24T17:11:24.336Z]   Clang :: dpct/codepin/report/option/test.cpp
[2024-09-24T17:11:24.336Z]   Clang :: dpct/fix_internal_error_2.cu
[2024-09-24T17:11:24.336Z]