Zero build on macOS fails after JDK-8303852

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how to reproduce:

./configure --with-jvm-variants=zero --with-debug-level=release
make images JOBS=32

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here shows the snippet of error log on my local environment, i.e. macOS on Apple silicon

=== Output from failing command(s) repeated here ===
* For target hotspot_variant-zero_libjvm_objs_os_bsd_zero.o:
~/jdk_src/src/hotspot/os_cpu/bsd_zero/os_bsd_zero.cpp:179:10: error: out-of-line declaration of a member must be a definition [-Wout-of-line-declaration]
void os::current_stack_base_and_size(address* base, size_t* size)
     ~~~~^
~/jdk_src/src/hotspot/os_cpu/bsd_zero/os_bsd_zero.cpp:179:66: error: expected ';' after top level declarator
void os::current_stack_base_and_size(address* base, size_t* size)
                                                                 ^
                                                                ;
~/jdk_src/src/hotspot/os_cpu/bsd_zero/os_bsd_zero.cpp:184:4: error: C++ requires a type specifier for all declarations
  *base = (address) pthread_get_stackaddr_np(self);
   ^
~/jdk_src/src/hotspot/os_cpu/bsd_zero/os_bsd_zero.cpp:185:4: error: C++ requires a type specifier for all declarations
  *size = pthread_get_stacksize_np(self);
   ^
~/jdk_src/src/hotspot/os_cpu/bsd_zero/os_bsd_zero.cpp:186:3: error: C++ requires a type specifier for all declarations
  bottom = *base - *size;
   ... (rest of output omitted)

* All command lines available in ~/build-release/make-support/failure-logs.
=== End of repeated output ===


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Fix:

Adding the missing opening brace would fix this build failure.