Fix CI build issue for Graviton (#1034)

CI was failing for the AMX specific test on ARM graviton. This patch
disables the AMX specific
test on ARM graviton to fix the CI build issue.

Author: shahidact

test/BF16/Integration/amx/lit.local.cfg

@@ -0,0 +1,48 @@
+import subprocess
+
+def has_support(feature):
+    # uArch detection not working on Windows
+    if sys.platform in ['win32']:
+        return False
+
+    try:
+        cmd = subprocess.Popen(
+            ['grep', feature, '/proc/cpuinfo'], stdout=subprocess.PIPE)
+    except OSError:
+        return False
+
+    out = cmd.stdout.read().decode('ascii')
+    cmd.wait()
+
+    if out == "":
+        return False
+
+    return True
+
+def is_arch(target):
+    # Arch detection not working on Windows
+    if sys.platform in ['win32']:
+        return False
+
+    try:
+        cmd = subprocess.Popen(
+            ['uname', '-m'], stdout=subprocess.PIPE)
+    except OSError:
+        return False
+
+    out = cmd.stdout.read().decode('ascii')
+    cmd.wait()
+
+    return target in out
+
+
+# Check if the target supports AMX BF16 instructions, disable tests if not
+# supported.
+if not has_support('amx_bf16'):
+    config.unsupported = True
+
+# Enable only on x86
+# Other targets may use different VNNI blocking scheme that is not compatible with
+# prepacked shapes in some of the tests
+if not is_arch('x86'):
+    config.unsupported = True

test/BF16/Integration/vector-contract-to-amx-gemm.mlir renamed to test/BF16/Integration/amx/vector-contract-to-amx-gemm.mlir

@@ -1,3 +1,5 @@
+// REQUIRES: target=x86{{.*}}
+
 // RUN: tpp-opt %s  --vector-contract-to-amx --split-input-file | FileCheck %s