Courgette: Add static method QuickDetect() to optimize program detection.

courgette/disassembler_elf_32_arm.h

Index: courgette/disassembler_elf_32_arm.h
diff --git a/courgette/disassembler_elf_32_arm.h b/courgette/disassembler_elf_32_arm.h
index 83f5dc6a237b8dc6cdd098ca3906c750227684c5..24b8aa83c7002b642ddb543ff0cb6c81b31b1a34 100644
--- a/courgette/disassembler_elf_32_arm.h
+++ b/courgette/disassembler_elf_32_arm.h
@@ -28,6 +28,11 @@ enum ARM_RVA {
 
 class DisassemblerElf32ARM : public DisassemblerElf32 {
  public:
+  // Returns true if a valid executable is detected using only quick checks.
+  static bool QuickDetect(const uint8_t* start, size_t length) {
+    return DisassemblerElf32::QuickDetect(start, length, EM_ARM);
+  }
+
   class TypedRVAARM : public TypedRVA {
    public:
     TypedRVAARM(ARM_RVA type, RVA rva) : TypedRVA(rva), type_(type) { }
@@ -47,7 +52,7 @@ class DisassemblerElf32ARM : public DisassemblerElf32 {
     const uint8_t* arm_op_;
   };
 
-  DisassemblerElf32ARM(const void* start, size_t length);
+  DisassemblerElf32ARM(const uint8_t* start, size_t length);
 
   ~DisassemblerElf32ARM() override { }