tci: fix build breakage for target-sparc

commit c28ae41e introduced GETPC() usage for sparc, which is currently
not defined when building with --enable-tcg-interpreter. Add sparc to
the list of targets we selectively define GETPC() for.
Signed-off-by: NMichael Roth <mdroth@linux.vnet.ibm.com>
Reviewed-by: NStefan Weil <sw@weilnetz.de>
Signed-off-by: NAurelien Jarno <aurelien@aurel32.net>

exec-all.h

@@ -296,7 +296,8 @@ extern int tb_invalidated_flag;
 #if defined(CONFIG_TCG_INTERPRETER)
 /* Alpha and SH4 user mode emulations and Softmmu call GETPC().
    For all others, GETPC remains undefined (which makes TCI a little faster. */
-# if defined(CONFIG_SOFTMMU) || defined(TARGET_ALPHA) || defined(TARGET_SH4)
+# if defined(CONFIG_SOFTMMU) || defined(TARGET_ALPHA) || defined(TARGET_SH4) \
+     || defined(TARGET_SPARC)
 extern uintptr_t tci_tb_ptr;
 #  define GETPC() tci_tb_ptr
 # endif