Revert "loongarch64: Add loongarch64 architecture detection support."

This reverts commit 0648830632e1426bc7d760c83307665307bb241a.

Reason for revert: Pending clarity on https://bugs.chromium.org/p/chromium/issues/detail?id=1361860

Original change's description:
> loongarch64: Add loongarch64 architecture detection support.
>
> Bug: 1361860
> Change-Id: I432208fd78fb99140a97b3979a257f4e2e513807
> Reviewed-on: https://chromium-review.googlesource.com/c/chromium/tools/depot_tools/+/3886536
> Commit-Queue: Robbie Iannucci <iannucci@chromium.org>
> Reviewed-by: Brian Ryner <bryner@google.com>
> Reviewed-by: Gavin Mak <gavinmak@google.com>

Bug: 1361860
Change-Id: Icf9f88a7173d4d403f4846fe01342794a0f5db9e
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/tools/depot_tools/+/4667669
Bot-Commit: Rubber Stamper <rubber-stamper@appspot.gserviceaccount.com>
Reviewed-by: Gavin Mak <gavinmak@google.com>
Commit-Queue: Robbie Iannucci <iannucci@chromium.org>
diff --git a/gclient.py b/gclient.py
index ac97dc0..6034617 100755
--- a/gclient.py
+++ b/gclient.py
@@ -1369,6 +1369,7 @@
         'checkout_mac': 'mac' in self.target_os,
         'checkout_win': 'win' in self.target_os,
         'host_os': _detect_host_os(),
+
         'checkout_arm': 'arm' in self.target_cpu,
         'checkout_arm64': 'arm64' in self.target_cpu,
         'checkout_x86': 'x86' in self.target_cpu,
@@ -1377,7 +1378,6 @@
         'checkout_ppc': 'ppc' in self.target_cpu,
         'checkout_s390': 's390' in self.target_cpu,
         'checkout_x64': 'x64' in self.target_cpu,
-        'checkout_loong64': 'loong64' in self.target_cpu,
         'host_cpu': detect_host_arch.HostArch(),
     }