When building QNX on MS-Windows, make magically adds the Msys root as
prefix to variables whose values look like paths; this applies to both
environment variables and variables given values on the command-line.
When we don't actually want to install under the Msys root, this is
unwelcome "help". So (for MinGW's make) support a magic prefix of our
own, @msyshack@, that'll make a path value for INSTALL_ROOT not look
like a path to make; we can then strip it off when we come to use it.
Change-Id: I951ad3c8fe3e5cfb49e6e361d7fff779f3a9d716
Reviewed-by: Jędrzej Nowacki <jedrzej.nowacki@theqtcompany.com>
Reviewed-by: Oswald Buddenhagen <oswald.buddenhagen@theqtcompany.com>
Reviewed-by: Frederik Gladhorn <frederik.gladhorn@theqtcompany.com>
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