Update the library paths to correctly refer to libdemo{1,2}_hexagon
and switch to the release build instead.

Update references to libstandalone to the specific G0/PIC archive instead.

(cherry picked from commit 647a453)

(cherry picked from commit 2aebe6c)

(cherry picked from commit 2c0030f)

(cherry picked from commit 0f21e45)

(cherry picked from commit 6ac035d)

This seems to fix two sporadic errors that have been appearing in CI.
One is an issue with cmake being unable to verify that cmake is able to
build a simple test program. The other is a `invalid r_symbolnum`
linking error when trying to build one of cranelift's tests.

This is intended as a temporary fix until we can figure out how to
resolve those issues.

(cherry picked from commit 4fd3cf9)

Allowing the Xcode version to "float" based on whatever default GitHub
selects creates an unreliable environment. When GitHub changes the
default, we can have multiple jobs in the same run using different
versions as it rolls out across machines. It can also cause oscillation
between runs as different machines are used. It also causes
unpredictable timing when the updates happen.

This change helps ensure that the version that is used is pinned. The
downside is that it requires manually bumping the version, and the risk
that if we take too long, older Xcodes will be removed and that will
break the build.

(cherry picked from commit 4ce1f1c)

(cherry picked from commit 83f3bc4)

(cherry picked from commit 7e1897c)