m68k/dpx2.h ASM_OUTPUT_SOURCE_FILENAME weirdness

[Zack Weinberg]

m68k/dpx2.h has

#undef ASM_OUTPUT_SOURCE_FILENAME
#define ASM_OUTPUT_SOURCE_FILENAME(FILE, NA)    \
  do { fprintf ((FILE), "\t.file\t'%s'\n", (NA)); } while (0)

The single quotes around the argument of .file are suspicious.  Is
this really the right definition?  Would the native Bull assembler
object to a double-quoted string here?  I don't want to add a special
output_quoted_string variant just for a machine that ceased production
in 1991.

zw