[NFC] Move enableAllExtensions out of header (#2459)

The list of extensions has grown considerably, which makes this
member function definition fairly large.  Move it out of the header.

Author: svenvh

include/LLVMSPIRVOpts.h

@@ -162,11 +162,7 @@ class TranslatorOpts {
     GenKernelArgNameMD = ArgNameMD;
   }
 
-  void enableAllExtensions() {
-#define EXT(X) ExtStatusMap[ExtensionID::X] = true;
-#include "LLVMSPIRVExtensions.inc"
-#undef EXT
-  }
+  void enableAllExtensions();
 
   void enableGenArgNameMD() { GenKernelArgNameMD = true; }
 

lib/SPIRV/LLVMSPIRVOpts.cpp

@@ -47,6 +47,12 @@
 using namespace llvm;
 using namespace SPIRV;
 
+void TranslatorOpts::enableAllExtensions() {
+#define EXT(X) ExtStatusMap[ExtensionID::X] = true;
+#include "LLVMSPIRVExtensions.inc"
+#undef EXT
+}
+
 bool TranslatorOpts::isUnknownIntrinsicAllowed(IntrinsicInst *II) const
     noexcept {
   if (!SPIRVAllowUnknownIntrinsics.has_value())