It seems that the Makefile has both CC and CFLAGS hardcoded and does not
allow overriding them by ones being passed by the buildsystem.
This works fine until CONFIG_PKG_ASLR_PIE_ALL is selected, then building
will fail with:
arm-openwrt-linux-muslgnueabi/bin/ld.bfd: mhz.o: relocation R_ARM_MOVW_ABS_NC against `a local symbol' can not be used when making a shared object; recompile with -fPIC
arm-openwrt-linux-muslgnueabi/bin/ld.bfd: mhz.o(.text+0x75c): unresolvable R_ARM_CALL relocation against symbol `__aeabi_l2d@@GCC_3.5
So, lets add a patch pending upstream that allows both CC and CFLAGS to be
overriden so that ones passed by the buildsystem are actually respected.
Fixes: 89123b308f ("mhz: add new package")
Signed-off-by: Robert Marko <robimarko@gmail.com>