Linux: Remove unused gcrypt gyp code.

build/linux/system.gyp

Index: build/linux/system.gyp
===================================================================
--- build/linux/system.gyp	(revision 274314)
+++ build/linux/system.gyp	(working copy)
@@ -7,12 +7,8 @@
     'conditions': [
       ['sysroot!=""', {
         'pkg-config': '<(chroot_cmd) ./pkg-config-wrapper "<(sysroot)" "<(target_arch)" "<(system_libdir)"',
-        # libgcrypt-config-wrapper invokes libgcrypt-config directly from the 
-        # sysroot, so there's no need to prefix it with <(chroot_cmd).
-        'libgcrypt-config': './libgcrypt-config-wrapper "<(sysroot)"',
       }, {
         'pkg-config': 'pkg-config',
-        'libgcrypt-config': 'libgcrypt-config',
       }],
     ],
 
@@ -793,27 +789,6 @@
       },
     },
     {
-      'target_name': 'libgcrypt',
-      'type': 'none',
-      'conditions': [
-        ['_toolset=="target" and use_cups==1', {
-          'direct_dependent_settings': {
-            'cflags': [
-              '<!@(<(libgcrypt-config) --cflags)',
-            ],
-          },
-          'link_settings': {
-            'libraries': [
-              # libgcrypt-config does not support --libs-only-l options,
-              # and the result contains -L options, which shouldn't be in
-              # the entries of 'libraries'. So filter them out.
-              '<!@(<(libgcrypt-config) --libs | sed -e \'s/-L[^ ]*//g\')',
-            ],
-          },
-        }],
-      ],
-    },
-    {
       'target_name': 'libpci',
       'type': 'static_library',
       'cflags': [