[llvm] [SLP][NFC] Use BoUpSLP::getNumberOfParts() where appropriate (PR #225995)

[Alexey Bataev via llvm-commits]

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@@ -26516,14 +26510,12 @@ void BoUpSLP::optimizeGatherSequence() {
     // Check if the last undefs actually change the final number of used vector
     // registers.
     return SM1.size() - LastUndefsCnt > 1 &&
-           slpvectorizer::getNumberOfParts(*TTI, SI1->getType(),
-                                           SI1->getType()->getElementType(),
-                                           SLPReVec) ==
-               slpvectorizer::getNumberOfParts(
-                   *TTI,
+           this->getNumberOfParts(SI1->getType(),
+                                  SI1->getType()->getElementType()) ==
+               this->getNumberOfParts(
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alexey-bataev wrote:

Drop `this->`

https://github.com/llvm/llvm-project/pull/225995