wsl/hsakmt: Remove pre-allocation free memory check

This change removes the check for sufficient free memory before allocation.
The previous check could cause performance degradation. Reserving a portion
of system memory helps prevent system hangs due to insufficient memory.
However, if free memory is still insufficient, memory allocation may still
lead to system hangs.

Signed-off-by: lyndonli <Lyndon.Li@amd.com>
Reviewed-by: Flora Cui <flora.cui@amd.com>
Part-of: <http://10.67.69.192/wsl/libhsakmt/-/merge_requests/10>

globals.cpp

@@ -44,4 +44,6 @@ bool is_svm_api_supported;
 /* zfb is mainly used during emulation */
 int zfb_support;
 /* handle vendor specific packet */
-int vendor_packet_support;
+int vendor_packet_support;
+
+size_t max_single_alloc_size = 0;