Use the static version of libc++ on Android

Remove the runtime dependency on libc++_shared.so for the
JIT flavor of beam.smp. This simplifies Erlang deployment
on Android as libc++ is not provided as a system library.
See https://developer.android.com/ndk/guides/cpp-support

Author: JeromeDeBretagne

xcomp/erl-xcomp-arm64-android.conf

@@ -127,7 +127,9 @@ CXX="aarch64-linux-$NDK_ABI_PLAT-clang++"
 LD="aarch64-linux-android-ld"
 
 # * `LDFLAGS' - Linker flags.
-#LDFLAGS=
+# Use the static version of libc++ provided by the Android NDK
+# when compiling the JIT flavor of the beam.smp executable.
+LDFLAGS="-static-libstdc++"
 
 # * `LIBS' - Libraries.
 #LIBS=

xcomp/erl-xcomp-x86_64-android.conf

@@ -101,7 +101,9 @@ CXX=x86_64-linux-$NDK_ABI_PLAT-clang++
 LD=x86_64-linux-android-ld.gold
 
 # * `LDFLAGS' - Linker flags.
-#LDFLAGS=
+# Use the static version of libc++ provided by the Android NDK
+# when compiling the JIT flavor of the beam.smp executable.
+LDFLAGS="-static-libstdc++"
 
 # * `LIBS' - Libraries.
 #LIBS=