Don't mask IRQs

[phil-opp]

Currently the bootloader masks all hardware interrupts:

bootloader/src/second_stage.s

Lines 68 to 71 in bda13d8

	disable_irqs:
	mov al, 0xFF # Out 0xFF to 0xA1 and 0x21 to disable all IRQs.
	out 0xA1, al
	out 0x21, al

They shouldn't be masked when control is passed to the kernel.

[robert-w-gries]

Hey Phil, are you saying that interrupts should be enabled when the bootloader jumps to _start()?

[phil-opp]

No, enabling them would not be a good idea since there isn't an IDT yet. I mean that they shouldn't be masked. An interrupt can be masked in the interrupt controller, so that the controller does not emit such an interrupt, even when interrupts are generally enabled.

Since this was patched, can we close the PR?

[phil-opp]

@rybot666 Yes, thanks for the hint!