||Don't forbid extensions to the dwp file
Section 7.3.5, pg 190
Section 7.3.5, p.190, line 10 says a package file "consists only of" various things.
Replace "consists only of" with "contains" to permit extensions.
As a very hypothetical example, this change permits a toolchain to link split DWARF
into the executable file, instead of separate .dwo/.dwp files. This potentially
simplifies split-DWARF management by permitting all .dwo/.dwp information to be kept
in the .o/executable files. While this tactic does not provide any link-time
improvements, it does provide the same improvements to debugger load time as the
original split-DWARF mechanism, while allowing users to manage only one actual file
(instead of an executable/.dwp pair of files).