Use system hunspell and quazip

Stop building its own bundled copies of quazip and hunspell.

Using bundled libraries is bad for several reasons [1], including breaking the
build, which happens with Qt 5.6 that passes -std=gnu++11 by default when the
compiler supports it:

hunspell/affentry.hxx:30:94: error: cannot initialize a parameter of type 'unsigned short' with an rvalue of type 'nullptr_t'
hunspell/affentry.hxx:93:103: error: cannot initialize a parameter of type 'unsigned short' with an rvalue of type 'nullptr_t'

Switching to the system versions fixes everything.

[1] https://www.freebsd.org/doc/en/books/porters-handbook/bundled-libs.html

PR: 212349
Approved by: portmgr (mat)