Support glibc compiled static ELF

Now emulator load every segments from binary except NULL address segments and `.bss`

Author: HexRabbit

emu-rv32i.c

@@ -2080,7 +2080,9 @@ int main(int argc, char** argv)
     scn = NULL;
     while ((scn = elf_nextscn(elf, scn)) != NULL) {
         gelf_getshdr(scn, &shdr);
-        if (shdr.sh_type == SHT_PROGBITS) {
+
+        /* filter NULL address segments and .bss */
+        if (shdr.sh_addr && shdr.sh_type != SHT_NOBITS) {
             Elf_Data *data = elf_getdata(scn, NULL);
             if (shdr.sh_addr >= ram_start) {
                 for (size_t i = 0; i < shdr.sh_size; i++) {