various devices used by hp9k_3xx.cpp: initialized some variables to fix problems found in devnoclear debug builds (nw)

src/devices/bus/hp_dio/hp98543.cpp

@@ -99,6 +99,7 @@ void dio16_98543_device::device_start()
 {
 	save_item(NAME(m_intreg));
 	save_item(NAME(m_ints));
+	m_intreg = 0;
 
 	dio().install_memory(
 			0x200000, 0x27ffff,

src/devices/bus/hp_dio/hp98643.cpp

@@ -95,6 +95,7 @@ void dio16_98643_device::device_start()
 	save_item(NAME(m_sc));
 	save_item(NAME(m_installed_io));
 	save_item(NAME(m_ram));
+	m_installed_io = false;
 }
 
 void dio16_98643_device::device_reset()

src/devices/bus/hp_dio/human_interface.cpp

@@ -141,6 +141,7 @@ void human_interface_device::device_reset()
 	m_gpib_irq_line = false;
 	m_kbd_nmi = false;
 	m_old_latch_enable = true;
+	m_gpib_dma_enable = false;
 	m_rtc->cs1_w(ASSERT_LINE);
 	m_rtc->cs2_w(CLEAR_LINE);
 	m_rtc->write_w(CLEAR_LINE);

src/devices/machine/tms9914.cpp

@@ -507,6 +507,9 @@ void tms9914_device::device_reset()
 	m_reg_parallel_p = 0;
 	m_reg_2nd_parallel_p = 0;
 
+	m_reg_ulpa = false;
+	std::fill(std::begin(m_ext_signals), std::end(m_ext_signals), false);
+
 	do_swrst();
 	update_fsm();
 	update_int();