[Driver][SYCL][FPGA] Enable -reuse-exe support for Windows (#2698)

-reuse-exe was not marked as a CoreOption, causing it not to
be accepted for clang-cl compilations.

Author: mdtoguchi

clang/include/clang/Driver/Options.td

@@ -3597,7 +3597,7 @@ defm underscoring : BooleanFFlag<"underscoring">, Group<gfortran_Group>;
 defm whole_file : BooleanFFlag<"whole-file">, Group<gfortran_Group>;
 
 // C++ SYCL options
-def reuse_exe_EQ : Joined<["-"], "reuse-exe=">,
+def reuse_exe_EQ : Joined<["-"], "reuse-exe=">, Flags<[CoreOption]>,
   HelpText<"Speed up FPGA aoc compile if the device code in <exe> is unchanged.">,
   MetaVarName<"<exe>">;
 def fsycl : Flag<["-"], "fsycl">, Group<sycl_Group>, Flags<[CC1Option, CoreOption]>,

clang/test/Driver/sycl-offload-intelfpga.cpp

@@ -224,6 +224,8 @@
 // RUN:  touch %t.cpp
 // RUN:  %clangxx -### -reuse-exe=testing -target x86_64-unknown-linux-gnu -fsycl -fintelfpga %t.cpp 2>&1 \
 // RUN:  | FileCheck -check-prefixes=CHK-FPGA-REUSE-EXE %s
+// RUN:  %clang_cl -### -reuse-exe=testing -fsycl -fintelfpga %t.cpp 2>&1 \
+// RUN:  | FileCheck -check-prefixes=CHK-FPGA-REUSE-EXE %s
 // CHK-FPGA-REUSE-EXE: aoc{{.*}} "-o" {{.*}} "-sycl" {{.*}} "-reuse-exe=testing"
 
 /// -fintelfpga dependency file generation test