Use same features for riscv32 as for arm and xtensa CPUs

rtl/freertos/system.cfg

@@ -230,6 +230,7 @@
 -SfCOMMANDARGS
 -SfRANDOM
 -SfRESOURCES
+-SfPROCESSES
 #endif CPURISCV32
 
 #ifdef CPURISCV64