Delete old x86 validator.

src/trusted/validator_x86/testdata/64/mov-esi-nop-use.test

-@hex:
-  # Case where we should conclude that the index register rsi in the second move contains
-  # only 32 bits, and is set by the mov, so it is legal (i.e. it zero extends).
-  # That is, the two moves:
-  #     mov %esi, %esi
-  #     mov [%r15 + %rsi*1 + 0x8], %edx
-  89 f6 \\
-  41 89 54 37 08
-@val:
-  VALIDATOR: Checking jump targets: 0 to 7
-  VALIDATOR: Checking that basic blocks are aligned
-  *** <input> is safe ***
-@rval:
-  VALIDATOR: Checking jump targets: 0 to 7
-  VALIDATOR: Checking that basic blocks are aligned
-  *** <input> is safe ***
-@rvald:
-  VALIDATOR: Checking block alignment and jump targets: 0 to 7
-  *** <input> is safe ***
-@vd-rval:
-  VALIDATOR: Checking jump targets: 0 to 7
-  VALIDATOR: Checking that basic blocks are aligned
-  *** <input> is safe ***
-@dis:
-  0000000000000000: 89 f6                                        mov %esi, %esi
-  0000000000000002: 41 89 54 37 08                               mov [%r15+%rsi*1+0x8], %edx
-@vdis:
-  0000000000000000: 89 f6                                        mov %esi, %esi
-  0000000000000002: 41 89 54 37 08                               mov [%r15+%rsi*1+0x8], %edx
-@rdfa_output:
-  return code: 0