overlays: mt8195_adsp: Update for gdb 12.1

Update the upstream file to build against recent gdb source (see
e.g. commit 34b88dc ("overlays: xtensa_nxp_imx8m_adsp: gdb:
Update xtensa-config.c")).

Signed-off-by: Andy Ross <andyross@google.com>

Author: andyross

overlays/xtensa_mtk_mt8195/gdb/gdb/xtensa-config.c

@@ -113,7 +113,7 @@ const xtensa_mask_t xtensa_mask39 = { 1, xtensa_submask39 };
 
 
 /* Register map.  */
-xtensa_register_t rmap[] = 
+static xtensa_register_t rmap[] =
 {
   /*    idx ofs bi sz al targno  flags cp typ group name  */
   XTREG(  0,  0,32, 4, 4,0x0020,0x0006,-2, 9,0x2100,pc,          0,0,0,0,0,0)
@@ -496,9 +496,4 @@ xtensa_register_t rmap[] =
   XTREG_END
 };
 
-
-
-#ifdef XTENSA_CONFIG_INSTANTIATE
-XTENSA_CONFIG_INSTANTIATE(rmap,16)
-#endif
-
+xtensa_gdbarch_tdep xtensa_tdep rmap);