Regenerate isa_test.bin from assembler (fixes CNTR opcode)

The old isa_test.bin was generated by gen_isa_test.py which had
a wrong opcode for CNTR (0x5000AF = REG1[15] = STACKA, should
be 0x3000AE = REG2[14] = CNTR).  Regenerated from isa_test.dsp
using open21xx assembler.

Also: to suppress the harmless 'asm.parser not found' warning,
use: r2 -e asm.parser=null -a adsp219x -b 24 firmware.bin
Or add 'e asm.parser=null' to ~/.radare2rc.

examples/build/regmap_test.dsp

@@ -0,0 +1,11 @@
+	.section/PM program0;
+	.global _start;
+_start:
+	cntr = 10;
+	stacka = 0x1000;
+	imask = 0xFF;
+	irptl = 0;
+	icntl = 0;
+	nop;
+_halt:
+	jump _halt;