Core: assume modern Unix has tm_gmtoff

Core/HLE/sceRtc.cpp:471:14: error: invalid argument type 'char *(*)(int, int)' to
      unary expression
                srcTick -= -timezone * 1000000ULL;
                           ^~~~~~~~~
Core/HLE/sceRtc.cpp:498:14: error: invalid argument type 'char *(*)(int, int)' to
      unary expression
                srcTick += -timezone * 1000000ULL;
                           ^~~~~~~~~
Core/HLE/sceRtc.cpp:1035:16: error: invalid argument type 'char *(*)(int, int)' to
      unary expression
                tz_seconds = -timezone;
                             ^~~~~~~~~
Core/HLE/sceRtc.cpp:1074:16: error: invalid argument type 'char *(*)(int, int)' to
      unary expression
                tz_seconds = -timezone;
                             ^~~~~~~~~
4 errors generated.

Core/HLE/sceRtc.cpp

@@ -459,16 +459,14 @@ static int sceRtcConvertLocalTimeToUTC(u32 tickLocalPtr,u32 tickUTCPtr)
 	{
 		u64 srcTick = Memory::Read_U64(tickLocalPtr);
 		// TODO : Let the user select his timezone / daylight saving instead of taking system param ?
-#if defined(__GLIBC__) || defined(BLACKBERRY) || defined(__SYMBIAN32__)
-		time_t timezone = 0;
-		tm *time = localtime(&timezone);
-		srcTick -= time->tm_gmtoff*1000000ULL;
-#elif defined(_MSC_VER)
+#ifdef _MSC_VER
 		long timezone_val;
 		_get_timezone(&timezone_val);
 		srcTick -= -timezone_val * 1000000ULL;
-#else
-		srcTick -= -timezone * 1000000ULL;
+#elif !defined(_AIX) && !defined(__sgi) && !defined(__hpux)
+		time_t timezone = 0;
+		tm *time = localtime(&timezone);
+		srcTick -= time->tm_gmtoff*1000000ULL;
 #endif
 		Memory::Write_U64(srcTick, tickUTCPtr);
 	}
@@ -486,16 +484,14 @@ static int sceRtcConvertUtcToLocalTime(u32 tickUTCPtr,u32 tickLocalPtr)
 	{
 		u64 srcTick = Memory::Read_U64(tickUTCPtr);
 		// TODO : Let the user select his timezone / daylight saving instead of taking system param ?
-#if defined(__GLIBC__) || defined(BLACKBERRY) || defined(__SYMBIAN32__)
-		time_t timezone = 0;
-		tm *time = localtime(&timezone);
-		srcTick += time->tm_gmtoff*1000000ULL;
-#elif defined(_MSC_VER)
+#ifdef _MSC_VER
 		long timezone_val;
 		_get_timezone(&timezone_val);
 		srcTick += -timezone_val * 1000000ULL;
-#else
-		srcTick += -timezone * 1000000ULL;
+#elif !defined(_AIX) && !defined(__sgi) && !defined(__hpux)
+		time_t timezone = 0;
+		tm *time = localtime(&timezone);
+		srcTick += time->tm_gmtoff*1000000ULL;
 #endif
 		Memory::Write_U64(srcTick, tickLocalPtr);
 	}
@@ -1023,16 +1019,14 @@ static int sceRtcFormatRFC2822LocalTime(u32 outPtr, u32 srcTickPtr)
 	}
 
 	int tz_seconds;
-#if defined(__GLIBC__) || defined(BLACKBERRY) || defined(__SYMBIAN32__)
-		time_t timezone = 0;
-		tm *time = localtime(&timezone);
-		tz_seconds = time->tm_gmtoff;
-#elif defined(_MSC_VER)
+#ifdef _MSC_VER
 		long timezone_val;
 		_get_timezone(&timezone_val);
 		tz_seconds = -timezone_val;
-#else
-		tz_seconds = -timezone;
+#elif !defined(_AIX) && !defined(__sgi) && !defined(__hpux)
+		time_t timezone = 0;
+		tm *time = localtime(&timezone);
+		tz_seconds = time->tm_gmtoff;
 #endif
 
 	DEBUG_LOG(SCERTC, "sceRtcFormatRFC2822LocalTime(%08x, %08x)", outPtr, srcTickPtr);
@@ -1062,16 +1056,14 @@ static int sceRtcFormatRFC3339LocalTime(u32 outPtr, u32 srcTickPtr)
 	}
 
 	int tz_seconds;
-#if defined(__GLIBC__) || defined(BLACKBERRY) || defined(__SYMBIAN32__)
-		time_t timezone = 0;
-		tm *time = localtime(&timezone);
-		tz_seconds = time->tm_gmtoff;
-#elif defined(_MSC_VER)
+#ifdef _MSC_VER
 		long timezone_val;
 		_get_timezone(&timezone_val);
 		tz_seconds = -timezone_val;
-#else
-		tz_seconds = -timezone;
+#elif !defined(_AIX) && !defined(__sgi) && !defined(__hpux)
+		time_t timezone = 0;
+		tm *time = localtime(&timezone);
+		tz_seconds = time->tm_gmtoff;
 #endif
 
 	DEBUG_LOG(SCERTC, "sceRtcFormatRFC3339LocalTime(%08x, %08x)", outPtr, srcTickPtr);