feat(drivers): HPET high-res timer, LPT parallel port, CMOS NVRAM

Add three real platform device drivers (x86 hardware, ARM-stubbed):

- drivers/timer/hpet.c + include/drivers/hpet.h: High Precision Event Timer.
  Maps the HPET block at the standard 0xFED00000, reads the femtosecond period
  from the capability register, enables the main counter and exposes a
  monotonic nanosecond time source (hpet_get_ns) far finer than the 100 Hz PIT.
- drivers/char/lpt.c + include/drivers/lpt.h: IBM PC parallel port (LPT1) with
  the Centronics data/strobe handshake over ports 0x378/0x379/0x37A.
- drivers/char/nvram.c + include/drivers/nvram.h: MC146818 CMOS NVRAM read/write
  over 0x70/0x71, preserving the NMI-disable bit, with checksum and hex dump.

Wired all three into the [5/14] device-enumeration boot step and added LazyBox
applets `hpet`, `lpt`, and `nvram`.

Verified live under QEMU (screenshotted): HPET reports 100 MHz / 3 comparators /
10 ns period and its counter advances ~1.4 s of real time between two `hpet`
runs; NVRAM dumps 128 bytes with a computed checksum; LPT1 detected at 0x378.
Clean build on x86_64/aarch64/armv8i; 0 panics / 0 OOM.

Co-Authored-By: Claude Opus 4.8 <[email protected]>
Claude-Session: https://claude.ai/code/session_01Fh5z6V7nGPbHvqVG5p4CXX

Makefile

@@ -277,7 +277,8 @@ endif
 # Common Input/Display/Power/GPU/Networking Drivers
 CONFIG_SRCS-y += drivers/char/tty.c drivers/char/keyboard.c drivers/char/serial.c drivers/char/vga.c \
                  drivers/input/mouse.c drivers/power/acpi.c drivers/power/cpufreq.c drivers/rtc/rtc.c drivers/sound/speaker.c \
-                 drivers/net/e1000e.c drivers/virtio/virtio_gpu.c drivers/virtio/virtio_input.c
+                 drivers/net/e1000e.c drivers/virtio/virtio_gpu.c drivers/virtio/virtio_input.c \
+                 drivers/timer/hpet.c drivers/char/lpt.c drivers/char/nvram.c
 
 # Userland & GUI Desktop Subsystem
 ifeq ($(CONFIG_USERLAND_LAZYBOX), y)