Fix pkgconfig dependencies (#39059)

pkg-config and pkgconf are providers.

var/spack/repos/builtin/packages/su2/package.py

@@ -53,7 +53,7 @@ class Su2(MesonPackage):
     depends_on("meson@0.61.1:", type=("build"))
     depends_on("python@3:", type=("build", "run"))
     depends_on("zlib")
-    depends_on("pkg-config")
+    depends_on("pkgconfig")
     depends_on("mpi", when="+mpi")
     depends_on("swig", type="build", when="+pywrapper")
     depends_on("py-mpi4py", when="+pywrapper")

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

@@ -77,7 +77,7 @@ class Whizard(AutotoolsPackage):
     depends_on("autoconf", type="build")
     depends_on("automake", type="build")
     depends_on("libtool", type="build")
-    depends_on("pkgconf", type="build")
+    depends_on("pkgconfig", type="build")
 
     conflicts(
         "%gcc@:5.0",