[PATCH] scripts/spelling.txt: remove 'thead' as a typo

[Drew Fustini <dfustini@baylibre.com>]

T-Head is a vendor of processor core IP, and they have recently
introduced the RISC-V TH1520 SoC. Remove 'thead' as a typo of 'thread'
to avoid checkpatch incorrectly warning that 'thead' is typo in patches
that add support for T-Head designs in the kernel.

Cc: Conor Dooley <conor@kernel.org>
Cc: Guo Ren <guoren@kernel.org>
Cc: Jisheng Zhang <jszhang@kernel.org>
Link: https://www.t-head.cn/
Signed-off-by: Drew Fustini <dfustini@baylibre.com>
---
 scripts/spelling.txt | 1 -
 1 file changed, 1 deletion(-)

For example, checkpatch prints the following warnings for 89b0186ab532
("dt-bindings: riscv: Add T-HEAD TH1520 board compatibles"):

  $ ./scripts/checkpatch.pl --strict -g 89b0186ab532
  WARNING: added, moved or deleted file(s), does MAINTAINERS need updating?
  new file mode 100644

  WARNING: 'thead' may be misspelled - perhaps 'thread'?
  +$id: http://devicetree.org/schemas/riscv/thead.yaml#
                                          ^^^^^

  WARNING: 'thead' may be misspelled - perhaps 'thread'?
  +          - const: thead,th1520
                    ^^^^^
  total: 0 errors, 3 warnings, 0 checks, 29 lines checked

The 'thead' typo false positive adds noise to automation like the
linux-riscv patchwork bot:
https://patchwork.kernel.org/project/linux-riscv/patch/20230722-upstream-beaglev-ahead-dts-v1-2-ccda511357f4@baylibre.com/

diff --git a/scripts/spelling.txt b/scripts/spelling.txt
index fc7ba95e86a0..855c4863124b 100644
--- a/scripts/spelling.txt
+++ b/scripts/spelling.txt
@@ -1541,7 +1541,6 @@ temeprature||temperature
 temorary||temporary
 temproarily||temporarily
 temperture||temperature
-thead||thread
 theads||threads
 therfore||therefore
 thier||their
-- 
2.34.1