[SYCL][TEST] Fix incorrect usage of host accessor

The test tries to create second host accessor to the buffer while the
first one still alive. This leads to hang.
The patch moves the first host accessor to the scope so it is destructed
before construction of the second host accessor.

Signed-off-by: Vlad Romanov <[email protected]>

Author: romanovvlad

sycl/test/basic_tests/buffer/buffer.cpp

@@ -655,11 +655,15 @@ int main() {
     cl::sycl::buffer<char, 1> Buf_1(Size);
     cl::sycl::buffer<char, 1> Buf_2(Size / 2);
 
-    auto AccA = Buf_1.get_access<cl::sycl::access::mode::read_write>(Size / 2);
-    auto AccB = Buf_2.get_access<cl::sycl::access::mode::read_write>(Size / 2);
-    assert(AccA.get_size() == AccB.get_size());
-    assert(AccA.get_range() == AccB.get_range());
-    assert(AccA.get_count() == AccB.get_count());
+    {
+      auto AccA =
+          Buf_1.get_access<cl::sycl::access::mode::read_write>(Size / 2);
+      auto AccB =
+          Buf_2.get_access<cl::sycl::access::mode::read_write>(Size / 2);
+      assert(AccA.get_size() == AccB.get_size());
+      assert(AccA.get_range() == AccB.get_range());
+      assert(AccA.get_count() == AccB.get_count());
+    }
 
     auto AH0 = accessor<char, 0, access::mode::read_write,
                         access::target::host_buffer>(Buf_1);