oniro.inc: Fix flavour name case in DISTRO_NAME

When DISTRO_NAME was refactored, it reused the lowercase variant of
flavour name changing in this way its style. This fixes it to use
the "pretty" flavour name.

Fixes #786



Signed-off-by: Andrei Gherzan <andrei.gherzan@huawei.com>

meta-oniro-core/conf/distro/include/oniro.inc

@@ -4,7 +4,7 @@
 
 ONIRO_FLAVOUR = "${@'${ONIRO_FLAVOUR_PRETTY}'.lower()}"
 DISTRO = "oniro-${ONIRO_FLAVOUR}"
-DISTRO_NAME = "Oniro Project Base ${ONIRO_FLAVOUR} Distro"
+DISTRO_NAME = "Oniro Project Base ${ONIRO_FLAVOUR_PRETTY} Distro"
 
 require conf/distro/include/security_flags.inc