mb/google/bluey: Select MISSING_BOARD_RESET due to lack of Chrome EC

The Bluey board configuration (`BOARD_GOOGLE_BLUEY`) now selects
`MISSING_BOARD_RESET`.

This change is necessary because Bluey does not have a Chrome EC.
Without a Chrome EC, a board-specific `do_board_reset()`
implementation, which often handles system shutdown or reset sequences
by interacting with an EC, is not feasible for Bluey.

As a result of selecting `MISSING_BOARD_RESET`:
- Bluey's `reset.c` is no longer compiled.
- If a board reset is triggered, the system will use the stub
  `do_board_reset()` provided when `CONFIG_MISSING_BOARD_RESET`
  is enabled.

This aligns Bluey's configuration with its hardware capabilities
regarding system reset.

BUG=b:404985109
TEST=Able to build google/bluey.

Change-Id: I2f770ce9e96544b7e1891a3d8ec84a1313210891
Signed-off-by: Subrata Banik <subratabanik@google.com>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/87677
Reviewed-by: Kapil Porwal <kapilporwal@google.com>
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>

src/mainboard/google/bluey/Kconfig

@@ -23,6 +23,7 @@ config BOARD_GOOGLE_BASEBOARD_BLUEY
 config BOARD_GOOGLE_BLUEY
 	select BOARD_GOOGLE_BASEBOARD_BLUEY
 	select MAINBOARD_HAS_FINGERPRINT_VIA_USB
+	select MISSING_BOARD_RESET
 
 if BOARD_GOOGLE_BLUEY_COMMON
 

src/mainboard/google/bluey/Makefile.mk

@@ -2,7 +2,9 @@
 
 all-y += boardid.c
 all-y += chromeos.c
+ifneq ($(CONFIG_MISSING_BOARD_RESET),y)
 all-y += reset.c
+endif
 
 bootblock-y += bootblock.c