[BT] Fix UART monitor init #486

Job	Run time
build (hw1, 3do)	2m 44s
build (hw1, cdi)	2m 52s
build (hw1, dreamcast)	2m 43s
build (hw1, gamecube)	2m 40s
build (hw1, gbahd)	2m 41s
build (hw1, genesis)	2m 52s
build (hw1, jaguar)	2m 44s
build (hw1, jvs_arcade)	2m 49s
build (hw1, n64)	2m 53s
build (hw1, nes)	2m 54s
build (hw1, parallel_1p)	2m 51s
build (hw1, parallel_1p_3v3)	2m 50s
build (hw1, parallel_2p)	2m 39s
build (hw1, parallel_2p_3v3)	2m 43s
build (hw1, pc_engine)	2m 51s
build (hw1, pcfx)	2m 40s
build (hw1, playstation)	2m 43s
build (hw1, saturn)	2m 43s
build (hw1, snes)	2m 42s
build (hw1, universal)	2m 59s
build (hw1, virtualboy)	2m 48s
build (hw1, wii_extension)	2m 41s
build (hw2, 3do)	2m 43s
build (hw2, cdi)	2m 39s
build (hw2, dreamcast)	2m 49s
build (hw2, gamecube)	2m 42s
build (hw2, gbahd)	2m 49s
build (hw2, genesis)	2m 34s
build (hw2, jaguar)	2m 42s
build (hw2, jvs_arcade)	2m 45s
build (hw2, n64)	2m 42s
build (hw2, nes)	2m 46s
build (hw2, parallel_1p)	2m 45s
build (hw2, parallel_1p_3v3)	2m 51s
build (hw2, parallel_2p)	2m 40s
build (hw2, parallel_2p_3v3)	2m 42s
build (hw2, pc_engine)	2m 44s
build (hw2, pcfx)	2m 45s
build (hw2, playstation)	2m 41s
build (hw2, saturn)	2m 50s
build (hw2, snes)	2m 50s
build (hw2, universal)	2m 40s
build (hw2, virtualboy)	2m 40s
build (hw2, wii_extension)	2m 44s
build (dbg, pad_test)	2m 54s
build (dbg, qemu)	2m 52s
build (dbg, qemu_bt_trace_replay)	2m 45s
build (dbg, qemu_bt_trace_replay_test)	2m 42s
package	6s
	2h 12m 24s

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