fix(main/termux-elf-cleaner): set default api-level to $TERMUX_PKG_API_LEVEL

So that users do not have to specify --api-level 24 or similar when
using the tool on-device.

Reported in termux/termux-packages#11612.

packages/termux-elf-cleaner/android-api-level.diff

@@ -0,0 +1,11 @@
+--- ./elf-cleaner.cpp~	2022-07-30 16:02:31.000000000 +0200
++++ ./elf-cleaner.cpp	2022-08-29 11:14:38.502827607 +0200
+@@ -50,7 +50,7 @@
+ 
+ /* Default to api level 21 unless arg --api-level given  */
+ uint8_t supported_dt_flags_1 = (DF_1_NOW | DF_1_GLOBAL);
+-int api_level = 21;
++int api_level = @TERMUX_PKG_API_LEVEL@;
+ 
+ bool dry_run = false;
+ bool quiet = false;

packages/termux-elf-cleaner/build.sh

@@ -5,11 +5,14 @@ TERMUX_PKG_MAINTAINER="@termux"
 # Please update checksum in termux_step_start_build.sh as well if
 # updating the package.
 TERMUX_PKG_VERSION=2.1.1
-TERMUX_PKG_REVISION=1
+TERMUX_PKG_REVISION=2
 TERMUX_PKG_SRCURL=https://github.com/termux/termux-elf-cleaner/archive/v${TERMUX_PKG_VERSION}.tar.gz
 TERMUX_PKG_SHA256=104231f91ef6662f80694fc4a59c6bfeae50da21c4fc22adac3c9a5aac00ba98
 TERMUX_PKG_DEPENDS="libc++"
 
 termux_step_pre_configure() {
 	autoreconf -vfi
+
+	sed "s%@TERMUX_PKG_API_LEVEL@%$TERMUX_PKG_API_LEVEL%g" \
+		"$TERMUX_PKG_BUILDER_DIR"/android-api-level.diff | patch --silent -p1
 }