Fix detour of functions returning a float

Floats are always returned in FPU register st0. Since the value in st0 doesn't matter in a pre-hook before the function was executed, don't try to save and restore the value of the FPU stack top for a pre-hook.
Only replace st0 after a post hook.

dynhooks_sourcepawn.cpp

@@ -387,7 +387,7 @@ ReturnAction_t HandleDetour(HookType_t hookType, CHook* pDetour)
 				}
 				else if (pWrapper->returnType == ReturnType_Float)
 				{
-					*(float *)tempRetBuf = *(float *)returnStruct->newResult;
+					*(float *)&tempRetBuf = *(float *)returnStruct->newResult;
 				}
 				else
 				{