Remove special cases in build-time dep audit

Closes Homebrew/homebrew#23931.

Formula/automake.rb

@@ -13,7 +13,7 @@ class Automake < Formula
   end
 
   # Always needs a newer autoconf, even on Snow Leopard.
-  depends_on 'autoconf'
+  depends_on 'autoconf' => :run
 
   if MacOS::Xcode.provides_autotools? or File.file? "/usr/bin/automake"
     keg_only "Xcode (up to and including 4.2) provides (a rather old) Automake."

Formula/graphicsmagick.rb

@@ -12,7 +12,7 @@ class Graphicsmagick < Formula
   option 'without-magick-plus-plus', 'disable build/install of Magick++'
   option 'without-svg', 'Compile without svg support'
 
-  depends_on :libltdl
+  depends_on :libtool => :run
 
   depends_on 'pkg-config' => :build
 

Formula/imagemagick.rb

@@ -24,7 +24,7 @@ class Imagemagick < Formula
   option 'with-perl', 'enable build/install of PerlMagick'
   option 'without-magick-plus-plus', 'disable build/install of Magick++'
 
-  depends_on :libltdl
+  depends_on :libtool => :run
 
   depends_on 'pkg-config' => :build
 

Formula/libextractor.rb

@@ -7,7 +7,7 @@ class Libextractor < Formula
   sha1 '244eb3e16dadedea9dc827fb91cb309e2baa8637'
 
   depends_on 'pkg-config' => :build
-  depends_on :libltdl
+  depends_on :libtool => :run
 
   def install
     ENV.deparallelize

Formula/libgphoto2.rb

@@ -8,7 +8,7 @@ class Libgphoto2 < Formula
   option :universal
 
   depends_on 'pkg-config' => :build
-  depends_on :libltdl # Configure script uses this
+  depends_on :libtool => :run
   depends_on 'libusb-compat'
   depends_on 'gd'
   depends_on 'libexif' => :optional

Formula/libp11.rb

@@ -11,7 +11,7 @@ class Libp11 < Formula
   end
 
   depends_on 'pkg-config' => :build
-  depends_on :libltdl
+  depends_on :libtool => :run
 
   def install
     system "./bootstrap" if build.head?

Formula/ruby-build.rb

@@ -7,8 +7,8 @@ class RubyBuild < Formula
 
   head 'https://github.com/sstephenson/ruby-build.git'
 
-  depends_on 'autoconf' => :recommended
-  depends_on 'pkg-config' => :recommended
+  depends_on 'autoconf' => [:recommended, :run]
+  depends_on 'pkg-config' => [:recommended, :run]
   depends_on 'libyaml' => :recommended
   depends_on 'openssl' => :optional