cmd/link: fix PE section attributes for windows/arm64
The clang-mingw toolchain on windows/arm64 expects
.text to NOT be listed as containing initialized data and
.dwarf* to be listed as containing initialized data.
Neither is true today, resulting in the go .text and .dwarf*
not being merged with the system .text and .dwarf*.
Having multiple .text and .dwarf* sections confuses all
kinds of tools.