jpeg: remove default flags

Jpeg 8c is the foundation of many libraries and applications.
It gets a minor checkup.  It had two configure flags listed in
the formula that were already the default. So those were removed.
No other changes were made, and the library and its dependents
do not need to be rebuilt.

Closes Homebrew/homebrew#7700.

Signed-off-by: Jack Nagel <jacknagel@gmail.com>

Formula/jpeg.rb

@@ -7,8 +7,8 @@ class Jpeg < Formula
   homepage 'http://www.ijg.org'
 
   def install
-    ENV.universal_binary
-    system "./configure", "--prefix=#{prefix}", "--disable-dependency-tracking", "--enable-shared", "--enable-static"
+    ENV.universal_binary   # Builds universal libs. Default is static & shared.
+    system "./configure", "--prefix=#{prefix}", "--disable-dependency-tracking"
     system "make install"
   end
 end