Expat is failing to build for freeradius3

Hi i am trying to compile freeradius3 , which is under package/feeds/packages , the error i am getting is

make -j1 -C /home/developer1/sep/openwrt_packages/openwrt-21.02/build_dir/hostpkg/expat-2.2.10
make[3]: Entering directory `/home/developer1/sep/openwrt_packages/openwrt-21.02/build_dir/hostpkg/expat-2.2.10'
make[4]: Entering directory `/home/developer1/sep/openwrt_packages/openwrt-21.02/build_dir/hostpkg/expat-2.2.10'
make[5]: Entering directory `/home/developer1/sep/openwrt_packages/openwrt-21.02/build_dir/hostpkg/expat-2.2.10'
make[5]: Leaving directory `/home/developer1/sep/openwrt_packages/openwrt-21.02/build_dir/hostpkg/expat-2.2.10'
make[5]: Entering directory `/home/developer1/sep/openwrt_packages/openwrt-21.02/build_dir/hostpkg/expat-2.2.10'
[ 25%] Building C object CMakeFiles/expat.dir/lib/xmlparse.c.o
/home/developer1/sep/openwrt_packages/openwrt-21.02/build_dir/hostpkg/expat-2.2.10/lib/xmlparse.c:109:4: error: #error You do not have support for any sources of high quality entropy enabled. For end user security, that is probably not what you want. Your options include: * Linux >=3.17 + glibc >=2.25 (getrandom): HAVE_GETRANDOM, * Linux >=3.17 + glibc (including <2.25) (syscall SYS_getrandom): HAVE_SYSCALL_GETRANDOM, * BSD / macOS >=10.7 (arc4random_buf): HAVE_ARC4RANDOM_BUF, * BSD / macOS (including <10.7) (arc4random): HAVE_ARC4RANDOM, * libbsd (arc4random_buf): HAVE_ARC4RANDOM_BUF + HAVE_LIBBSD, * libbsd (arc4random): HAVE_ARC4RANDOM + HAVE_LIBBSD, * Linux (including <3.17) / BSD / macOS (including <10.7) (/dev/urandom): XML_DEV_URANDOM, * Windows >=Vista (rand_s): _WIN32. If insist on not using any of these, bypass this error by defining XML_POOR_ENTROPY; you have been warned. If you have reasons to patch this detection code away or need changes to the build system, please open a bug. Thank you!
 #  error You do not have support for any sources of high quality entropy \
    ^
make[5]: *** [CMakeFiles/expat.dir/lib/xmlparse.c.o] Error 1
make[5]: Leaving directory `/home/developer1/sep/openwrt_packages/openwrt-21.02/build_dir/hostpkg/expat-2.2.10'
make[4]: *** [CMakeFiles/expat.dir/all] Error 2
make[4]: Leaving directory `/home/developer1/sep/openwrt_packages/openwrt-21.02/build_dir/hostpkg/expat-2.2.10'
make[3]: *** [all] Error 2
make[3]: Leaving directory `/home/developer1/sep/openwrt_packages/openwrt-21.02/build_dir/hostpkg/expat-2.2.10'
make[2]: *** [/home/developer1/sep/openwrt_packages/openwrt-21.02/build_dir/hostpkg/expat-2.2.10/.built] Error 2
make[2]: Leaving directory `/home/developer1/sep/openwrt_packages/openwrt-21.02/feeds/packages/libs/expat'
time: package/feeds/packages/expat/host-compile#0.14#0.01#0.28
    ERROR: package/feeds/packages/expat [host] failed to build.

This error is getting resolved if we are giving #define XML_POOR_ENTROPY 1 in expact_compat.h file as it is un tar file i tried applying patch but patch is not getting applied.
Could someone please help
Thanks in advance.