Kernel: Explicitly initialize bools in IOAPIC mapping

The compiler couldn't convince itself that these are always initialized
when compiling with Og. They are always initialized before use, because
the only branch where they weren't had VERIFY_NOT_REACHED.

Kernel/Interrupts/IOAPIC.cpp

@@ -48,7 +48,7 @@ void IOAPIC::map_interrupt_redirection(u8 interrupt_vector)
     for (auto redirection_override : InterruptManagement::the().isa_overrides()) {
         if (redirection_override.source() != interrupt_vector)
             continue;
-        bool active_low;
+        bool active_low = false;
         // See ACPI spec Version 6.2, page 205 to learn more about Interrupt Overriding Flags.
         switch ((redirection_override.flags() & 0b11)) {
         case 0:
@@ -64,7 +64,7 @@ void IOAPIC::map_interrupt_redirection(u8 interrupt_vector)
             break;
         }
 
-        bool trigger_level_mode;
+        bool trigger_level_mode = false;
         // See ACPI spec Version 6.2, page 205 to learn more about Interrupt Overriding Flags.
         switch (((redirection_override.flags() >> 2) & 0b11)) {
         case 0:
@@ -116,7 +116,7 @@ void IOAPIC::map_isa_interrupts()
     for (auto redirection_override : InterruptManagement::the().isa_overrides()) {
         if ((redirection_override.gsi() < gsi_base()) || (redirection_override.gsi() >= (gsi_base() + m_redirection_entries_count)))
             continue;
-        bool active_low;
+        bool active_low = false;
         // See ACPI spec Version 6.2, page 205 to learn more about Interrupt Overriding Flags.
         switch ((redirection_override.flags() & 0b11)) {
         case 0:
@@ -132,7 +132,7 @@ void IOAPIC::map_isa_interrupts()
             break;
         }
 
-        bool trigger_level_mode;
+        bool trigger_level_mode = false;
         // See ACPI spec Version 6.2, page 205 to learn more about Interrupt Overriding Flags.
         switch (((redirection_override.flags() >> 2) & 0b11)) {
         case 0: