fix: add llvm-libs to AUR makedepends

Fixes #97 — on minimal Arch installs, rustc fails with
"error while loading shared libraries: libLLVM.so" because
llvm-libs isn't pulled in transitively.

PKGBUILD

@@ -9,7 +9,7 @@ url="https://github.com/razvandimescu/numa"
 license=('MIT')
 options=('!lto')
 depends=('gcc-libs' 'glibc')
-makedepends=('cargo' 'git')
+makedepends=('cargo' 'git' 'llvm-libs')
 provides=("$_pkgname")
 conflicts=("$_pkgname")
 backup=('etc/numa.toml')