libicu: Respect TZ environment variable

packages/libicu/build.sh

@@ -6,6 +6,7 @@ TERMUX_PKG_LICENSE="BSD"
 TERMUX_PKG_LICENSE_FILE="../LICENSE"
 TERMUX_PKG_MAINTAINER="@termux"
 TERMUX_PKG_VERSION=69.1
+TERMUX_PKG_REVISION=1
 TERMUX_PKG_SRCURL=https://github.com/unicode-org/icu/releases/download/release-${TERMUX_PKG_VERSION//./-}/icu4c-${TERMUX_PKG_VERSION//./_}-src.tgz
 TERMUX_PKG_SHA256=4cba7b7acd1d3c42c44bb0c14be6637098c7faf2b330ce876bc5f3b915d09745
 TERMUX_PKG_DEPENDS="libc++"

packages/libicu/source-common-putil.cpp.patch

@@ -0,0 +1,17 @@
+--- ./common/putil.cpp	2021-10-20 07:38:51.711938975 +0530
++++ ./common/putil.cpp.mod	2021-10-20 07:40:29.671938937 +0530
+@@ -1132,10 +1132,11 @@
+ 
+ /* This code can be temporarily disabled to test tzname resolution later on. */
+ #ifndef DEBUG_TZNAME
+-#if U_PLATFORM == U_PF_ANDROID
+-    tzid = gAndroidTimeZone;
+-#else
+     tzid = getenv("TZ");
++#if U_PLATFORM == U_PF_ANDROID
++    if (tzid == NULL) {
++        tzid = gAndroidTimeZone;
++    }
+ #endif
+     if (tzid != NULL && isValidOlsonID(tzid)
+ #if U_PLATFORM == U_PF_SOLARIS