treewide: assemble all fetchurlBoot uses in overrides to fetchurl itself

The only outside-curl uses of `fetchurlBoot` left are `stdenv`
and `apple-source-releases`. The latter one can probably be removed
too, but I can't test it.

Pros:

- Aggregates all behind-the-scenes insanity in a single place.

Cons:

- At the cost of 10 more derivations (but 0 new outpaths).

pkgs/development/interpreters/perl/default.nix

@@ -1,4 +1,4 @@
-{ lib, stdenv, fetchurlBoot, buildPackages
+{ lib, stdenv, fetchurl, buildPackages
 , enableThreading ? stdenv ? glibc, makeWrapper
 }:
 
@@ -27,7 +27,7 @@ let
 
     name = "perl-${version}";
 
-    src = fetchurlBoot {
+    src = fetchurl {
       url = "mirror://cpan/src/5.0/${name}.tar.gz";
       inherit sha256;
     };
@@ -46,7 +46,7 @@ let
       ]
       ++ optional (versionOlder version "5.29.6")
         # Fix parallel building: https://rt.perl.org/Public/Bug/Display.html?id=132360
-        (fetchurlBoot {
+        (fetchurl {
           url = "https://rt.perl.org/Public/Ticket/Attachment/1502646/807252/0001-Fix-missing-build-dependency-for-pods.patch";
           sha256 = "1bb4mldfp8kq1scv480wm64n2jdsqa3ar46cjp1mjpby8h5dr2r0";
         })
@@ -156,7 +156,7 @@ let
   } // stdenv.lib.optionalAttrs (stdenv.buildPlatform != stdenv.hostPlatform) rec {
     crossVersion = "276849e62f472c1b241d9e7b38a28e4cc9f98563"; # Dez 02, 2018
 
-    perl-cross-src = fetchurlBoot {
+    perl-cross-src = fetchurl {
       url = "https://github.com/arsv/perl-cross/archive/${crossVersion}.tar.gz";
       sha256 = "1fpr1m9lgkwdp1vmdr0s6gvmcpd0m8q6jwn024bkczc2h37bdynd";
     };