autotools: Fix find races on source directory

In a similar way to http://git.yoctoproject.org/cgit.cgi/poky/commit/?id=aa1438b56f30515f9c31b306decef7f562dda81f


there are more find races in the autotools class.

For recipes with PACKAGES_remove = "${PN}", the find which removes
.la files can race against deletion of other directories in WORKDIR
e.g.:
find: '/home/autobuilder/yocto-autobuilder/yocto-worker/nightly-oe-selftest/build/build/tmp/work/qemux86_64-poky-linux/init-ifupdown/1.0-r7/sstate-build-populate_lic': No such file or directory
| WARNING: /home/autobuilder/yocto-autobuilder/yocto-worker/nightly-oe-selftest/build/build/tmp/work/qemux86_64-poky-linux/init-ifupdown/1.0-r7/temp/run.do_configure.6558:1 exit 1 from
| find /home/autobuilder/yocto-autobuilder/yocto-worker/nightly-oe-selftest/build/build/tmp/work/qemux86_64-poky-linux/init-ifupdown/1.0-r7 -name \*.la -delete

Fix the remaining races in the same way.

[YOCTO #7522]

Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>