gdb: fix "p" command to print module variables correctly

Some objects format may potentially support copy relocations, but
currently the maybe_copied is always initialized to 0 in the symbol().
And the type is 'mst_file_bss', not always the 'mst_bss' or 'mst_data'
in the lookup_minimal_symbol_linkage(). For example:

(gdb) p *msymbol
$42 = {<general_symbol_info> = {m_name = 0x349812f "test_no_static", value = {ivalue = 8, block = 0x8,
      bytes = 0x8 <error: Cannot access memory at address 0x8>, address = 8, common_block = 0x8, chain = 0x8}, language_specific = {
      obstack = 0x0, demangled_name = 0x0}, m_language = language_auto, ada_mangled = 0, section = 20}, size = 4,
  filename = 0x6db3440 "test_sanity.c", type = mst_file_bss, created_by_gdb = 0, target_flag_1 = 0, target_flag_2 = 0, has_size = 1,
  maybe_copied = 0, name_set = 1, hash_next = 0x0, demangled_hash_next = 0x0}

This causes a problem that the 'p' command cannot work well as expected,
and emits an error or a bogus value:

  crash> mod -s test_sanity /home/test_sanity.ko
       MODULE       NAME                         BASE           SIZE  OBJECT FILE
  ffffffffc1084040  test_sanity            ffffffffc1082000    16384  /home/test_sanity.ko
  crash> p test_no_static
  p: gdb request failed: p test_no_static
  crash>

The issue occurs with Linux 6.2 and later or kernels that have kernel
commit 80e4c1cd42ff ("x86/retbleed: Add X86_FEATURE_CALL_DEPTH") and
configured with CONFIG_CALL_DEPTH_TRACKING=y, including RHEL9.3 and
later kernels.

With the patch:
  crash> mod -s test_sanity /home/test_sanity.ko
       MODULE       NAME                         BASE           SIZE  OBJECT FILE
  ffffffffc1084040  test_sanity            ffffffffc1082000    16384  /home/test_sanity.ko
  crash> p test_no_static
  test_no_static = $1 = 5
  crash>

Signed-off-by: Lianbo Jiang <[email protected]>

Author: lian-bo

gdb-10.2.patch

@@ -16094,3 +16094,27 @@ exit 0
 +{
 +  loongarch_elf_fpregset.collect_regset (NULL, regcache, regno, fpregset, sizeof (prfpregset_t));
 +}
+--- gdb-10.2/gdb/minsyms.c.orig
++++ gdb-10.2/gdb/minsyms.c
+@@ -535,7 +535,9 @@ lookup_minimal_symbol_linkage (const char *name, struct objfile *objf)
+ 	{
+ 	  if (strcmp (msymbol->linkage_name (), name) == 0
+ 	      && (MSYMBOL_TYPE (msymbol) == mst_data
+-		  || MSYMBOL_TYPE (msymbol) == mst_bss))
++		  || MSYMBOL_TYPE (msymbol) == mst_bss
++		  || MSYMBOL_TYPE (msymbol) == mst_file_bss
++		  || MSYMBOL_TYPE (msymbol) == mst_file_data))
+ 	    return {msymbol, objfile};
+ 	}
+     }
+--- gdb-10.2/gdb/symtab.h.orig
++++ gdb-10.2/gdb/symtab.h
+@@ -1110,7 +1110,7 @@ struct symbol : public general_symbol_info, public allocate_on_obstack
+       is_objfile_owned (1),
+       is_argument (0),
+       is_inlined (0),
+-      maybe_copied (0),
++      maybe_copied (1), /* The objfile potentially supports copy relocations. */
+       subclass (SYMBOL_NONE)
+     {
+       /* We can't use an initializer list for members of a base class, and