icu: bump to version 55.1

Signed-off-by: Gustavo Zacarias <gustavo@zacarias.com.ar>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>

package/icu/icu.hash

@@ -1,2 +1,2 @@
-# From https://ssl.icu-project.org/files/icu4c/54.1/icu4c-src-54_1.md5
-md5	e844caed8f2ca24c088505b0d6271bc0	icu4c-54_1-src.tgz
+# From https://ssl.icu-project.org/files/icu4c/55.1/icu4c-src-55_1.md5
+md5	e2d523df79d6cb7855c2fbe284f4db29	icu4c-55_1-src.tgz

package/icu/icu.mk

@@ -4,7 +4,7 @@
 #
 ################################################################################
 
-ICU_VERSION = 54.1
+ICU_VERSION = 55.1
 ICU_SOURCE = icu4c-$(subst .,_,$(ICU_VERSION))-src.tgz
 ICU_SITE = http://download.icu-project.org/files/icu4c/$(ICU_VERSION)
 ICU_LICENSE = ICU License