gcc48: remove upstreamed patch
postgres92: find tcl on Xcode-only

Refs Homebrew/homebrew#32337.
Remove lua52

Yanks Lua52 out of Homebrew-Versions - Is being merged into the main
branch alongside Lua. Lua52 will become Lua, the current Lua will become
Lua51. This PR relates to [this
PR](https://github.com/Homebrew/homebrew/pull/32059).

Closes #519.

Signed-off-by: Jack Nagel <jacknagel@gmail.com>
gcc48: fix audit warning
llvm35: fix build on 10.7 and 10.8
llvm35: optionally build lld

Closes #525.

Signed-off-by: Jack Nagel <jacknagel@gmail.com>