riscv: pgtable: Cleanup useless VA_USER_XXX definitions

These marcos are not used after commit b5b4287 ("riscv: mm: Use
hint address in mmap if available"). Cleanup VA_USER_XXX definitions
in asm/pgtable.h.

Fixes: b5b4287 ("riscv: mm: Use hint address in mmap if available")
Signed-off-by: Guo Ren (Alibaba DAMO Academy) <guoren@kernel.org>
Reviewed-by: Jinjie Ruan <ruanjinjie@huawei.com>
Link: https://patch.msgid.link/20251201005850.702569-1-guoren@kernel.org
Signed-off-by: Paul Walmsley <pjw@kernel.org>

Author: guoren83

arch/riscv/include/asm/pgtable.h

@@ -124,10 +124,6 @@
 #ifdef CONFIG_64BIT
 #include <asm/pgtable-64.h>
 
-#define VA_USER_SV39 (UL(1) << (VA_BITS_SV39 - 1))
-#define VA_USER_SV48 (UL(1) << (VA_BITS_SV48 - 1))
-#define VA_USER_SV57 (UL(1) << (VA_BITS_SV57 - 1))
-
 #define MMAP_VA_BITS_64 ((VA_BITS >= VA_BITS_SV48) ? VA_BITS_SV48 : VA_BITS)
 #define MMAP_MIN_VA_BITS_64 (VA_BITS_SV39)
 #define MMAP_VA_BITS (is_compat_task() ? VA_BITS_SV32 : MMAP_VA_BITS_64)