gitignore: Ignore binutils linker temp stXXXXXX objects

Fixes #40607.

Co-authored-by: Hugo Locurcio <hugo.locurcio@hugo.pro>
(cherry picked from commit 5e8b188365)

.gitignore

@@ -33,6 +33,8 @@ platform/android/java/lib/.cxx/
 *.os
 *.Plo
 *.lo
+# Binutils tmp linker output of the form "stXXXXXX" where "X" is alphanumeric
+st[A-Za-z0-9][A-Za-z0-9][A-Za-z0-9][A-Za-z0-9][A-Za-z0-9][A-Za-z0-9]
 
 # Libs generated files
 .deps/*