drm/i915/perf: remove redundant variable 'taken'

The assignment to variable taken is redundant and so it can be
removed as well as the variable too.

Cleans up clang-scan build warnings:
warning: Although the value stored to 'taken' is used in the enclosing
expression, the value is never actually read from 'taken'
[deadcode.DeadStores]

Signed-off-by: Colin Ian King <colin.i.king@gmail.com>
Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Signed-off-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20221007195345.2749911-1-colin.i.king@gmail.com

drivers/gpu/drm/i915/i915_perf.c

@@ -656,7 +656,6 @@ static int gen8_append_oa_reports(struct i915_perf_stream *stream,
 	size_t start_offset = *offset;
 	unsigned long flags;
 	u32 head, tail;
-	u32 taken;
 	int ret = 0;
 
 	if (drm_WARN_ON(&uncore->i915->drm, !stream->enabled))
@@ -692,7 +691,7 @@ static int gen8_append_oa_reports(struct i915_perf_stream *stream,
 
 
 	for (/* none */;
-	     (taken = OA_TAKEN(tail, head));
+	     OA_TAKEN(tail, head);
 	     head = (head + report_size) & mask) {
 		u8 *report = oa_buf_base + head;
 		u32 *report32 = (void *)report;
@@ -950,7 +949,6 @@ static int gen7_append_oa_reports(struct i915_perf_stream *stream,
 	size_t start_offset = *offset;
 	unsigned long flags;
 	u32 head, tail;
-	u32 taken;
 	int ret = 0;
 
 	if (drm_WARN_ON(&uncore->i915->drm, !stream->enabled))
@@ -984,7 +982,7 @@ static int gen7_append_oa_reports(struct i915_perf_stream *stream,
 
 
 	for (/* none */;
-	     (taken = OA_TAKEN(tail, head));
+	     OA_TAKEN(tail, head);
 	     head = (head + report_size) & mask) {
 		u8 *report = oa_buf_base + head;
 		u32 *report32 = (void *)report;