rtase: Modify the condition used to detect overflow in rtase_calc_time_mitigation

[ Upstream commit 68f9d89 ]

Fix the following compile error reported by the kernel test
robot by modifying the condition used to detect overflow in
rtase_calc_time_mitigation.

In file included from include/linux/mdio.h:10:0,
                  from drivers/net/ethernet/realtek/rtase/rtase_main.c:58:
 In function 'u16_encode_bits',
     inlined from 'rtase_calc_time_mitigation.constprop' at drivers/net/
     ethernet/realtek/rtase/rtase_main.c:1915:13,
     inlined from 'rtase_init_software_variable.isra.41' at drivers/net/
     ethernet/realtek/rtase/rtase_main.c:1961:13,
     inlined from 'rtase_init_one' at drivers/net/ethernet/realtek/
     rtase/rtase_main.c:2111:2:
>> include/linux/bitfield.h:178:3: error: call to '__field_overflow'
      declared with attribute error: value doesn't fit into mask
    __field_overflow();     \
    ^~~~~~~~~~~~~~~~~~
 include/linux/bitfield.h:198:2: note: in expansion of macro
 '____MAKE_OP'
   ____MAKE_OP(u##size,u##size,,)
   ^~~~~~~~~~~
 include/linux/bitfield.h:200:1: note: in expansion of macro
 '__MAKE_OP'
  __MAKE_OP(16)
  ^~~~~~~~~

Reported-by: kernel test robot <lkp@intel.com>
Closes: https://lore.kernel.org/oe-kbuild-all/202503182158.nkAlbJWX-lkp@intel.com/
Fixes: a36e9f5 ("rtase: Add support for a pci table in this module")
Signed-off-by: Justin Lai <justinlai0215@realtek.com>
Reviewed-by: Simon Horman <horms@kernel.org>
Link: https://patch.msgid.link/20250424040444.5530-1-justinlai0215@realtek.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>

Author: Justin Lai

drivers/net/ethernet/realtek/rtase/rtase_main.c

@@ -1924,8 +1924,8 @@ static u16 rtase_calc_time_mitigation(u32 time_us)
 
 	time_us = min_t(int, time_us, RTASE_MITI_MAX_TIME);
 
-	msb = fls(time_us);
-	if (msb >= RTASE_MITI_COUNT_BIT_NUM) {
+	if (time_us > RTASE_MITI_TIME_COUNT_MASK) {
+		msb = fls(time_us);
 		time_unit = msb - RTASE_MITI_COUNT_BIT_NUM;
 		time_count = time_us >> (msb - RTASE_MITI_COUNT_BIT_NUM);
 	} else {