Refactor rel32 searching process for x64 to make it more similar to x86.

courgette/testdata/rel32_win32_x86_04.txt

-# Test false detection cases.
-
-# .text start RVA and end RVA
-1000
-3000
-# .reloc start RVA and end RVA
-3800
-4000
-# End RVA
-5000
-
-# Assume ImageBase = 00400000. This does not affect the test.
-Program:
-  00401000: 55                 push        ebp
-  00401001: 8B EC              mov         ebp,esp
-  00401003: B8 E8 00 00 00     mov         eax,0E8h  # E8 00 00 00 00
-  00401008: 00 C0              add         al,al
-  0040100A: 90                 nop
-  0040100B: 90                 nop
-  0040100C: B9 00 00 00 E9     mov         ecx,0E9000000h  # E9 E8 00 00 00
-  00401011: E8 00 00 00 00     call        00401016
-  00401016: 90                 nop
-  00401017: 90                 nop
-  00401018: B1 0F              mov         cl,0Fh  # 0F 80 C0 00 00 00
-  0040101A: 80 C0 00           add         al,0
-  0040101D: 00 00              add         byte ptr [eax],al
-  0040101F: 90                 nop
-  00401020: 90                 nop
-  00401021: B8 E8 00 00 00     mov         eax,0E8h  # E8 00 00 00 E8
-  00401026: E8 00 00 00 00     call        0040102B
-  0040102B: 90                 nop
-  0040102C: 90                 nop
-  0040102D: E8 00 E9 00 00     call        0040F932  # E9 00 00 00 00
-  00401032: 00 00              add         byte ptr [eax],al
-  00401034: 5D                 pop         ebp
-  00401035: C3                 ret
-
-Abs32:
-
-Expected:
-1005  # False positive
-1011  # False positive
-# 1012 => False negative: shadowed by 1011
-101B  # False positive
-# 1023 => Potential false positive, but suppressed since target is outside .text
-1027  # Emerges since it's not shadowed by 1023
-1030  # False positive: target of 102E was outside .text, so fall back to this