Delete old x86 validator.

src/trusted/validator_x86/testdata/64/stosd-bad.test

-@hex:
-  # Show an example of an invalid (implicit) reference to a segment register
-  # (in this case missing a 32-bit zero extending operation before the LEA):
-  #
-  #   lea %rdi, [%r15+%rdi*1]
-  #   stosd
-  49 8d 3c 3f
-  ab
-@val:
-  VALIDATOR: 0000000000000004: ab                                           stosd [%rdi]
-  VALIDATOR: ERROR: Segment memory reference not allowed
-  VALIDATOR: Checking jump targets: 0 to 5
-  VALIDATOR: Checking that basic blocks are aligned
-  *** <input> IS UNSAFE ***
-@rval:
-  VALIDATOR: 0000000000000004: ab                                           stosd [%rdi]
-  VALIDATOR: ERROR: Segment memory reference not allowed
-  VALIDATOR: Checking jump targets: 0 to 5
-  VALIDATOR: Checking that basic blocks are aligned
-  *** <input> IS UNSAFE ***
-@rvald:
-  VALIDATOR: 0000000000000004: ab                                           stosd [%rdi]
-  VALIDATOR: ERROR: Segment memory reference not allowed
-  VALIDATOR: Checking block alignment and jump targets: 0 to 5
-  *** <input> IS UNSAFE ***
-@vd-rval:
-  VALIDATOR: 0000000000000004: ab                                           [P] dontcare [%rdi] (s), %eax (u)
-  VALIDATOR: ERROR: Segment memory reference not allowed
-  VALIDATOR: Checking jump targets: 0 to 5
-  VALIDATOR: Checking that basic blocks are aligned
-  *** <input> IS UNSAFE ***
-@dis:
-  0000000000000000: 49 8d 3c 3f                                  lea %rdi, [%r15+%rdi*1]
-  0000000000000004: ab                                           stosd [%rdi]
-@vdis:
-  0000000000000000: 49 8d 3c 3f                                  lea %rdi, [%r15+%rdi*1]
-  0000000000000004: ab                                           [P] dontcare [%rdi] (s), %eax (u)
-@rdfa_output:
-  4: [0] unrecognized instruction
-  return code: 1