x86/boot: Remove unused symbols from linker script

The symbols declared with DECLARE_IMPORT are meant to be
used by the 32 bit code.
The __base_relocs_{start,end} symbols were not used by the
code.
No functional changes.

Reported-by: Jan Beulich <jbeulich@suse.com>
Signed-off-by: Frediano Ziglio <frediano.ziglio@cloud.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>

xen/arch/x86/boot/build32.lds.S

@@ -43,8 +43,6 @@ SECTIONS
          * Attention should be paid to pointers taking care of possible later
          * relocation.
          */
-        DECLARE_IMPORT(__base_relocs_start);
-        DECLARE_IMPORT(__base_relocs_end);
         DECLARE_IMPORT(__trampoline_rel_start);
         DECLARE_IMPORT(__trampoline_rel_stop);
         DECLARE_IMPORT(__trampoline_seg_start);