arm64/sysreg: Fix typo in Enum element regex

In the awk script, there was a typo with the comparison operator when
checking if the matched pattern is inside an Enum block.
This prevented the generation of the whole sysreg-defs.h header.

Fixes: 66847e0618 ("arm64: Add sysreg header generation scripting")
Signed-off-by: Alejandro Tafalla <atafalla@dnyon.com>
Reviewed-by: Mark Brown <broonie@kernel.org>
Link: https://lore.kernel.org/r/20220609204220.12112-1-atafalla@dnyon.com
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>

arch/arm64/tools/gen-sysreg.awk

@@ -253,7 +253,7 @@ END {
 	next
 }
 
-/0b[01]+/ && block = "Enum" {
+/0b[01]+/ && block == "Enum" {
 	expect_fields(2)
 	val = $1
 	name = $2