eal/windows: fix build with recent MinGW

[ upstream commit c6221c664e52a94baf259a29ea73645496502af1 ]

Windows compilation with cross-mingw on Fedora 39 failed
because MEM_REPLACE_PLACEHOLDER and MEM_RESERVE_PLACEHOLDER were
already defined in the compiler environment:

eal_memory.c:77: error: "MEM_REPLACE_PLACEHOLDER" redefined
/usr/x86_64-w64-mingw32/sys-root/mingw/include/winnt.h:5710: note:
this is the location of the previous definition

eal_memory.c:78: error: "MEM_RESERVE_PLACEHOLDER" redefined
/usr/x86_64-w64-mingw32/sys-root/mingw/include/winnt.h:5715: note:
this is the location of the previous definition

The patch masks MEM_REPLACE_PLACEHOLDER and MEM_RESERVE_PLACEHOLDER
macros if they were pre-defined by compiler.

The patch also masks MEM_COALESCE_PLACEHOLDERS and
MEM_PRESERVE_PLACEHOLDER to prevent similar errors.

Fixes: 2a5d547 ("eal/windows: implement basic memory management")

Signed-off-by: Gregory Etelson <getelson@nvidia.com>
Acked-by: Tyler Retzlaff <roretzla@linux.microsoft.com>
Acked-by: Dmitry Kozlyuk <dmitry.kozliuk@gmail.com>
Acked-by: Thomas Monjalon <thomas@monjalon.net>

lib/librte_eal/windows/eal_memory.c

@@ -72,10 +72,18 @@ static VirtualAlloc2_type VirtualAlloc2_ptr;
 
 #ifdef RTE_TOOLCHAIN_GCC
 
+#ifndef MEM_COALESCE_PLACEHOLDERS
 #define MEM_COALESCE_PLACEHOLDERS 0x00000001
+#endif
+#ifndef MEM_PRESERVE_PLACEHOLDER
 #define MEM_PRESERVE_PLACEHOLDER  0x00000002
+#endif
+#ifndef MEM_REPLACE_PLACEHOLDER
 #define MEM_REPLACE_PLACEHOLDER   0x00004000
+#endif
+#ifndef MEM_RESERVE_PLACEHOLDER
 #define MEM_RESERVE_PLACEHOLDER   0x00040000
+#endif
 
 int
 eal_mem_win32api_init(void)