Add -znodelete linker option

This option is needed for openssl to create a correct library.

Author: hermantb

libtcc.c

@@ -1457,6 +1457,8 @@ static int tcc_set_linker(TCCState *s, const char *optarg)
             s->filetype |= AFF_WHOLE_ARCHIVE;
         } else if (link_option(&o, "no-whole-archive")) {
             s->filetype &= ~AFF_WHOLE_ARCHIVE;
+        } else if (link_option(&o, "znodelete")) {
+            s->znodelete = 1;
 #ifdef TCC_TARGET_PE
         } else if (link_option(&o, "large-address-aware")) {
             s->pe_characteristics |= 0x20;

tcc.h

@@ -741,6 +741,7 @@ struct TCCState {
     unsigned char static_link; /* if true, static linking is performed */
     unsigned char rdynamic; /* if true, all symbols are exported */
     unsigned char symbolic; /* if true, resolve symbols in the current module first */
+    unsigned char znodelete; /* Set DF_1_NODELETE in dynamic section */
     unsigned char filetype; /* file type for compilation (NONE,C,ASM) */
     unsigned char optimize; /* only to #define __OPTIMIZE__ */
     unsigned char option_pthread; /* -pthread option */

tccelf.c

@@ -2939,6 +2939,8 @@ static int elf_output_file(TCCState *s1, const char *filename)
                 put_dt(dynamic, DT_TEXTREL, 0);
             if (file_type & TCC_OUTPUT_EXE)
                 dt_flags_1 = DF_1_NOW | DF_1_PIE;
+	    if (s1->znodelete)
+		dt_flags_1 |= DF_1_NODELETE;
         }
         put_dt(dynamic, DT_FLAGS, DF_BIND_NOW);
         put_dt(dynamic, DT_FLAGS_1, dt_flags_1);