pulseaudio: add pkgconfig build dep (#45653)

Signed-off-by: Teague Sterling <teaguesterling@gmail.com>

var/spack/repos/builtin/packages/pulseaudio/package.py

@@ -55,6 +55,7 @@ class Pulseaudio(AutotoolsPackage):
     depends_on("libxtst", when="+x11")
     depends_on("openssl", when="+openssl")
     depends_on("perl-xml-parser", type="build")
+    depends_on("pkgconfig", type="build")
     depends_on("speexdsp@1.2:")
     depends_on("m4", type="build")