boards: xenvm: remove incorrect condition for Kconfig heap values

xenvm Kconfig contained incorrect name for board parameter. It led to
build issues - heap size was set incorrectly. Since whole file is
already placed under right Kconfig condition ("if BOARD_XENVM"), remove
incorrect parameter at all.

This issue was introduced by commit 8dc3f85 ("hwmv2: Introduce
Hardware model version 2 and convert devices") due to the typo.

Signed-off-by: Dmytro Firsov <[email protected]>

Author: firscity

boards/xen/xenvm/Kconfig.defconfig

@@ -7,6 +7,6 @@ config BUILD_OUTPUT_BIN
 	default y
 
 config HEAP_MEM_POOL_SIZE
-	default 16384 if BOARD_XENVM_XENVM
+	default 16384
 
 endif # BOARD_XENVM