This patch fixes linker errors about duplicate symbols seen when compiling OpenBLAS using Flang on windows.
Flang string literals are globals with linkonce linkage and identical strings in different files get the same
hashed names. They are handled properly on Linux but cause a linker duplicate symbol error on windows.
Another solution would have been to change the linkage for string literals in Flang to private but I am not
sure if that's appropriate.
I am not very familiar with linkers so please let me know if something seems wrong.