zephyr: kconfig: replace LOG_INPLACE_PROCESS setting w/ LOG_IMMEDIATE

Commit 1d9e5ee1 ("logging: Refactoring 'in place' mode to reduce memory
footprint") changed the resource restrained version of LOGGER from
LOG_INPLACE_PROCESS to LOG_IMMEDIATE.

Signed-off-by: Michael Scott <mike@foundries.io>
Signed-off-by: Andrzej Puzdrowski <andrzej.puzdrowski@nordicsemi.no>
diff --git a/boot/zephyr/Kconfig b/boot/zephyr/Kconfig
index 2d2e05e..5f645ff 100644
--- a/boot/zephyr/Kconfig
+++ b/boot/zephyr/Kconfig
@@ -137,7 +137,7 @@
 	bool "MCUboot have logging enabled"
 	default y
 	select LOG
-	select LOG_INPLACE_PROCESS
+	select LOG_IMMEDIATE
 	help
 	  If y, enables logging on the serial port. The log level can
 	  be defined by setting `LOG_DEFAULT_LEVEL`.