Build gnat for cross building from x86_64 to armv7 with OS runtime.

Build gnat for cross building from x86_64 to armv7 with OS runtime.

[Nick Kostyria]

Hello.
I have gcc12 and gnat12 on x86_64 freebsd.
I succeed build gnat for cross building to i386 and to aarch64.
But I got error when i try to build for armv7.
I do not want to build for SMT32 or other board on arm. 
I want to build for  cross building to freebsd on armv7.

Received error is:

/usr/ports/devel/freebsd-gnat12/work-armv7/.build/./gcc/xgcc -B/usr/ports/devel/freebsd-gnat12/work-armv7/.build/./gcc/ -B/usr/local/gnat12/armv7-gnueabi-freebsd13.1/bin/ -B/usr/local/gnat12/armv7-gnueabi-freebsd13.1/lib/ -isystem /usr/local/gnat12/armv7-gnueabi-freebsd13.1/include -isystem /usr/local/gnat12/armv7-gnueabi-freebsd13.1/sys-include --sysroot=/usr/local/freebsd-sysroot/armv7   -c -g -O2   -W -Wall -gnatpg -nostdinc   a-assert.adb -o a-assert.o
fatal error, run-time library not installed correctly
cannot locate file system.ads
compilation abandoned
gmake[7]: *** [../gcc-interface/Makefile:301: a-assert.o] Error 1
gmake[7]: Leaving directory '/usr/ports/devel/freebsd-gnat12/work-armv7/.build/gcc/ada/rts'

I suspect that there's a try to build with STM32 runtime. It's true?
`

What should I add to the configuration to get arm OS runtime, like with aarch64?

./configure --target=armv7-gnueabi-freebsd13.1 --disable-nls --enable-languages="c,ada" \
                --enable-gnu-indirect-function  \
                --with-sysroot="/" \
                --with-build-sysroot="/usr/local/freebsd-sysroot/armv7" \
                --with-as=/usr/local/bin/arm-gnueabi-freebsd13.1-as      \
                --with-ld=/usr/local/bin/arm-gnueabi-freebsd13.1-ld      \
                --enable-threads=posix  \
                --disable-libquadmath   \
                --enable-host-shared    \
                --disable-libmudflap    \
                --with-system-zlib      \
                --disable-libgomp       \
                --disable-libssp        \
                --enable-libada         \
                --without-zstd

Thanks.