Add test for ldr Rd, =label on ARM.

Currently, =label is interpreted as a string instead of a symbol.

suite/regress/arm_ldr_label.py

+#!/usr/bin/python
+# Ingmar Steen, 2016
+
+# This tests the LDR Rd, =label pseudo-instruction on ARM.
+
+# Fill in the information in the form below when you create a new regression
+
+# Github issue: #46
+# Author: Ingmar Steen
+
+from keystone import *
+
+import regress
+
+class TestARM(regress.RegressTest):
+    def runTest(self):
+        # Initialize Keystone engine
+        ks = Ks(KS_ARCH_ARM, KS_MODE_ARM)
+        # Assemble to get back insn encoding & statement count
+        encoding, count = ks.asm(b"ldr r0, =data; data:")
+        # Assert the result
+        self.assertEqual(encoding, [ 0x04, 0x00, 0x1f, 0xe5, 0x04, 0x00, 0x00, 0x00 ])
+
+if __name__ == '__main__':
+    regress.main()