MAINTAINERS: Cover include/sysemu/accel-blocker.h

Commit bd688fc931 "accel: introduce accelerator blocker API" aded
include/sysemu/accel-blocker.h and accel/accel-blocker.c.  MAINTAINERS
covers the latter in section "Guest CPU Cores (other accelerators) /
Overall", but not the former.  Fix that.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20230119091545.3116376-3-armbru@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>

MAINTAINERS

@@ -437,7 +437,7 @@ M: Richard Henderson <richard.henderson@linaro.org>
 R: Paolo Bonzini <pbonzini@redhat.com>
 S: Maintained
 F: include/qemu/accel.h
-F: include/sysemu/accel-ops.h
+F: include/sysemu/accel-*.h
 F: include/hw/core/accel-cpu.h
 F: accel/accel-*.c
 F: accel/Makefile.objs