fix LedDeviceWs2812SPI to compile on gcc 4.6 (#643)

* Removed -HUP so the default -TERM signal is sent instead.
- hyperiond only listens for TERM and INT. HUP is often used to get an exe to reread its config

Changed pgrep to add '-x' so it wont partial match on the exe name.
- I have multiple instances with multiple hyperiond-instance1 names
- this ensures the service script only kills the right process

* reversing errant change to hyperion.systemd.sh

* cleaned up a couple of compiler warnings

* moved bitpair_to_byte initialiser to (hopefully) work with older GCC

* compiler warning in udp driver
removed some tabs in ws2812b.cpp

* formatting - spaces to tabs


Former-commit-id: 42cc7325177c9fcc3d1bd29cbfe72f02118d3233

libsrc/leddevice/LedDeviceWs2812SPI.h

@@ -42,11 +42,5 @@ private:
 	size_t mLedCount;
 	std::vector<uint8_t> _spiBuffer;
 
-        uint8_t bitpair_to_byte[4] = {
-                0b10001000,
-                0b10001100,
-                0b11001000,
-                0b11001100,
-        };
-
+        uint8_t bitpair_to_byte[4];
 };