Explicitly specify encoding for export definition file, and add BOM.
Explicitly specify encoding for export definition file, and add BOM.

See https://docs.microsoft.com/en-us/cpp/build/reference/unicode-support-in-the-compiler-and-linker?view=msvc-160#linker-response-files-and-def-files.

phst/rules_elisp,phst/rules_elisp,phst/rules_elisp,phst/rules_elisp,phst/rules_elisp