bfd: cast BFD_ALIGN to fix clang error on mips

error: implicit conversion from 'bfd_vma' (aka 'unsigned long long')
to 'int' changes value from 18446744073709551615 to -1
  return BFD_ALIGN (ret, 16);
  ~~~~~~ ^~~~~~~~~~~~~~~~~~~
note: expanded from macro 'BFD_ALIGN'
   : ~ (bfd_vma) 0)
     ^~~~~~~~~~~~~

Sponsored by:	The FreeBSD Foundation

contrib/binutils/bfd/ecoff.c

@@ -1878,7 +1878,7 @@ _bfd_ecoff_sizeof_headers (bfd *abfd,
   ret = (bfd_coff_filhsz (abfd)
 	 + bfd_coff_aoutsz (abfd)
 	 + c * bfd_coff_scnhsz (abfd));
-  return BFD_ALIGN (ret, 16);
+  return (int) BFD_ALIGN (ret, 16);
 }
 
 /* Get the contents of a section.  */