fix(disasm): name the amd64 families x/arch decodes to the zero opcode

x/arch reports the ADCX, ADOX, RDSEED, RDPID, TPAUSE, UMONITOR, UMWAIT
and ENDBR families with no error but the degenerate zero instruction,
which GoSyntax renders as Op(0) under its prefix decoration and with a
length of one.  A supplementary naming table keyed by the opcode
pattern restores the toolchain's own spellings and lengths; the parity
fixtures pin all 41 corpus rows (ENDBR32 alone, which the toolchain
cannot spell, pins as bytes and text in the focused naming test).

Assisted-by: GLM 5.3 Flash

disasm/testdata/parity_amd64_unlisted.txt

@@ -1188,3 +1188,43 @@ c4e17c77	VZEROALL
 c4e17877	VZEROUPPER
 0f09	WBINVD
 f30faed2	WRFSBASE DX
+660f38f613	ADCXL 0(BX), DX
+66410f38f613	ADCXL 0(R11), DX
+660f38f6d2	ADCXL DX, DX
+66410f38f6d3	ADCXL R11, DX
+66440f38f61b	ADCXL 0(BX), R11
+66450f38f61b	ADCXL 0(R11), R11
+66440f38f6da	ADCXL DX, R11
+66450f38f6db	ADCXL R11, R11
+66480f38f613	ADCXQ 0(BX), DX
+66490f38f613	ADCXQ 0(R11), DX
+66480f38f6d2	ADCXQ DX, DX
+66490f38f6d3	ADCXQ R11, DX
+664c0f38f61b	ADCXQ 0(BX), R11
+664d0f38f61b	ADCXQ 0(R11), R11
+664c0f38f6da	ADCXQ DX, R11
+664d0f38f6db	ADCXQ R11, R11
+f30f38f613	ADOXL 0(BX), DX
+f3410f38f613	ADOXL 0(R11), DX
+f30f38f6d2	ADOXL DX, DX
+f3410f38f6d3	ADOXL R11, DX
+f3440f38f61b	ADOXL 0(BX), R11
+f3450f38f61b	ADOXL 0(R11), R11
+f3440f38f6da	ADOXL DX, R11
+f3450f38f6db	ADOXL R11, R11
+f3480f38f613	ADOXQ 0(BX), DX
+f3490f38f613	ADOXQ 0(R11), DX
+f3480f38f6d2	ADOXQ DX, DX
+f3490f38f6d3	ADOXQ R11, DX
+f34c0f38f61b	ADOXQ 0(BX), R11
+f34d0f38f61b	ADOXQ 0(R11), R11
+f34c0f38f6da	ADOXQ DX, R11
+f34d0f38f6db	ADOXQ R11, R11
+660fc7fa	RDSEEDW DX
+66410fc7fb	RDSEEDW R11
+f30fc7fa	RDPID DX
+f3410fc7fb	RDPID R11
+660faef3	TPAUSE BX
+f30faef3	UMONITOR BX
+f20faef3	UMWAIT BX
+f30f1efa	ENDBR64