treewide: pkgs.pkgconfig -> pkgs.pkg-config, move pkgconfig to alias.nix

continuation of #109595

pkgconfig was aliased in 2018, however, it remained in
all-packages.nix due to its wide usage. This cleans
up the remaining references to pkgs.pkgsconfig and
moves the entry to aliases.nix.

python3Packages.pkgconfig remained unchanged because
it's the canonical name of the upstream package
on pypi.

pkgs/development/compilers/crystal/build-package.nix

@@ -1,4 +1,4 @@
-{ stdenv, lib, crystal, shards, git, pkgconfig, which, linkFarm, fetchFromGitHub, installShellFiles }:
+{ stdenv, lib, crystal, shards, git, pkg-config, which, linkFarm, fetchFromGitHub, installShellFiles }:
 
 {
   # Some projects do not include a lock file, so you can pass one
@@ -61,7 +61,7 @@ stdenv.mkDerivation (mkDerivationArgs // {
   buildInputs = args.buildInputs or [ ] ++ [ crystal ]
     ++ lib.optional (format != "crystal") shards;
 
-  nativeBuildInputs = args.nativeBuildInputs or [ ] ++ [ git installShellFiles pkgconfig which ];
+  nativeBuildInputs = args.nativeBuildInputs or [ ] ++ [ git installShellFiles pkg-config which ];
 
   buildPhase = args.buildPhase or (lib.concatStringsSep "\n" ([
     "runHook preBuild"

pkgs/development/compilers/crystal/default.nix

@@ -18,7 +18,7 @@
 , makeWrapper
 , openssl
 , pcre
-, pkgconfig
+, pkg-config
 , readline
 , tzdata
 , which
@@ -134,7 +134,7 @@ let
 
         buildInputs = commonBuildInputs extraBuildInputs;
 
-        nativeBuildInputs = [ binary makeWrapper which pkgconfig llvmPackages.llvm ];
+        nativeBuildInputs = [ binary makeWrapper which pkg-config llvmPackages.llvm ];
 
         makeFlags = [
           "CRYSTAL_CONFIG_VERSION=${version}"
@@ -158,7 +158,7 @@ let
 
           install -Dm755 .build/crystal $bin/bin/crystal
           wrapProgram $bin/bin/crystal \
-            --suffix PATH : ${lib.makeBinPath [ pkgconfig llvmPackages.clang which ]} \
+            --suffix PATH : ${lib.makeBinPath [ pkg-config llvmPackages.clang which ]} \
             --suffix CRYSTAL_PATH : lib:$lib/crystal \
             --suffix CRYSTAL_LIBRARY_PATH : ${
               lib.makeLibraryPath (commonBuildInputs extraBuildInputs)